I'm going to be exploring almost every feature of each site and comparing it with the other site. One point will be rewarded to the site whose feature is better.

Signing Up


SwagBucks
Signing up for SwagBucks is easy. You can either go to their website and sign up, or you can click another user's referral link and then sign up.
Lockerz
To sign up for Lockerz you need to receive an E-Mail invitation from another user. There is no signing up on their site and there is no referral link. You have to give someone else your E-Mail address so they can send you the invitation. It is a great idea, that way the users get more points because they have more people to invite, but it would be much better if their was atleast a referral link. Another thing that needs improvement is in the sign up form. It asks for your phone number. Most users become hesitant when seeing that and think the website is fake.
Overall view of Signing Up
SwagBucks and Lockerz both have their perks, but being forced to have to sign up under someone else gives Lockerz the lead. Many SwagBucks users miss out on referral points because most people sign up on their own. With Lockerz' system, everyone wins.

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Earning Points

SwagBucks
Earning points for SwagBucks is very (very) difficult if you are not popular on the internet. It's easy to earn points by referring people, but unfortunately you only earn points from the referral if the person you refer earns points. This can be very good or very bad. Most people aren't popular on the internet so earning points on SwagBucks is usually difficult. You can earn points by searching which will most likely give you 1-2 points a day and you can look around for SwagCodes which are hard to find unless you are on the internet constantly. They almost always give you a mere 1 point and aren't available everyday. There is also a video game trade-in program and a used cell phone trade-in program. Don't trade in your video games! They give you less points than you deserve. Use another website that gives you money instead. The cell trade-in is still underpaying you, but there aren't many other places to trade them in so it's not so bad if you trad in old cell phones here. You can also shop and earn. On websites that are partnered with them, you get one point for every five dollars spent. It's great if you are a big spender but useless if you aren't planning on buying anything. Every once and a while there are also special ways to get points like sending in pictures of yourself in a swagbucks T-shirt, submitting the best poll out of thousands of people, or making a YouTube video. These opportunities don't come often though. An average number of points per day is around 3 if you don't refer people. The effort level to get points is very high so if you don't put effort in you will get around 1 point per day.
Lockerz
So far Lockerz has three ways to earn points (they call them ptz and so will I from now on). You can refer and instantly earn 2 ptz when the person you refer signs up, unlike SwagBucks. The next way to earn ptz is to sign in. If you sign in you will recieve 2 ptz. Although you can only get 2 ptz a day from signing in, it's still a ridiculously easy way to earn. The last way to earn is by answering the dailies. There is one question each day and if you answer it the day it's posted then you recieve 2 ptz. It doesn't require complex answers either, just put something simple. There's also something called the Z-list. If you refer 20 people you earn double the ptz! It's an amazing and easy deal. you also receive a free T-Shirt! The average of ptz per day is 4 without referring people and it only takes 5 minutes to earn that! Very simple!
Overall view of Earning Points
Although SwagBucks has more ways to earn points, it requires much more effort and you still earn an average of less points. Lockerz is easy and quick with earning.

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Point Value

SwagBucks
Points aren't worth much at SwagBucks. Unless you refer many people, you have no chance at getting anything expensive (unless you use it like crazy for atleast 2 years).
Lockerz
Lockerz ptz have a very high value. You don't need to refer people to earn expensive prizes.
Overall
Lockerz easily wins. Here are a few point comparisons. An iPod Touch at Swagbucks is 3000 points, while an iPod Touch at Lockerz is only 600. A PSP 3000 is 3165 points at SwagBucks. At Lockerz it is 100. The prizes will rise at Lockerz when it is out of beta but I doubt it will be anything close to that high.

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Prizes

SwagBucks
SwagBucks has a huge variety of prizes that are almost always in stock. 
Lockerz
Lockerz range of prizes is pretty small and is out of stock often. They are still in beta though so their should be more prizes and more in stock in the near future.
Overall
SwagBucks easily wins

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Server


SwagBucks
I haven't noticed any downtime on their server. Their website is always working and its somewhat fast. The only problems that I have experienced are when you click links on their search engine. They sometimes don't work unless you refresh. Not bad at all.
Lockerz
Since Lockerz is new, they weren't prepared for the huge increase of users. They have had a lot of downtime recently and the site was very slow. This problem occurs less often now, but it still occurs (such as right now, as I'm writing this).
Overall
SwagBucks wins. In the future, when Lockerz has more experience, than it will definitely be more stable and fast. SwagBucks has been around for a while

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Customer Service

SwagBucks
To be honest, I do not enjoy SwagBucks customer service. They haven't answered some of my questions from a month ago! In fact, they've never answered any of my questions.
Lockerz
Although Lockerz is brand new and very busy, they've answered both of my questions within 6 hours of asking them (one answer was around 6 minutes from when I asked). 
Overall
Lockerz wins this, without a doubt.

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Entertainment

SwagBucks
SwagBucks provides some entertainment. Since you aren't sure when you are going to win, it's always more exciting when you do. They also have a blog, Twitter trivia, a regular Twitter page, and a YouTube page.
Lockerz
Could use some work. Nothing really entertaining yet. Their two main entertainment sections will be released with the official release of Lockerz. They have a Twitter page and dailies. That's basically it.
Overall
SwagBucks has the upperhand, but that will most likely change in the future.

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