The Main Program:
BzzAgent is a word of mouth (WOM) product testing program. They send you a product (often full size) or a coupon to get the product free in store in your "BzzKit". You try the product then spread your honest opinion online and in person. Sometimes your kit comes with samples or coupons to pass out to friends, family, or even strangers. After doing this, you report back on how you spread the word. The methods of doing this seem to change every few months. It used to be that you would just do a BzzReport. You would explain how you shared and what was said. Those are still available but there are other ways of sharing that vary from campaign to campaign. Some campaigns have the options to post a photo or write a review or tweet about it on Twitter. This sounds more time consuming and laborsome than it actually is. The reporting/sharing is not work at all as you are usually so excited to share that you got the item free that you want to talk about it. The actions that follow take anywhere from a minute to about ten. My husband actually joined during 2013 and joined at a great time for guys because they were the target demographic for several campaigns in a row. He got to test razors (free razors are never turned down by a military man), Dr. Scholls, some toys for the kids, etc.
Your BzzKit is the main reward and point of the program. I have gotten anything from three packs of gum (5 gum was one of my first campaigns) to an $179 Sonicare toothbrush for free! If you are near a Kroger (or affiliate) store, you are VERY lucky as they do Kroger exclusive campaigns frequently. Unfortunately I am no longer near one :(
When certain actions are approved or when you take certain surveys, you get points for the Mypoints program. This site I have been through even longer than BzzAgent. The points that you earn can be turned in for gift cards for many different stores, restaurants, and more. While I don't shop through MyPoints (I use Shopathome almost exclusively as explained here), it is an option. You can also earn points for surveys (I usually don't bother on this site), taking quick polls, printing and using coupons, and "reading" (really just clicking the link) emails. I have gotten many restaurant gift cards to treat the family to a night out.
--Patience is key with this program! You might get lucky and get a campaign offer within a week. You also might have to wait a few months to get picked. It's worth the wait. You don't do much while you are waiting. Make sure your surveys are up to date (once you get through the ones that are there when you join, there are very few throughout the year) as this is what they use to pick people. Even after you work your BzzScore up to a high number, you can have some months where you have multiple simultaneous campaigns, then go several months without any invitations.
--Quality over quantity when you are doing the actions. A few actions scored "excellent" is better than many marked "fair". Do try to do at least 2-3 actions per campaign though.
--Your actions expire after one year. This will affect your overall BzzScore so if it drops and you check that all of your surveys are done, there is nothing to worry about.
--While most campaigns are free, there are occasionally ones that are just for discounts. You do NOT ever have to accept a campaign that you do not want to do (no matter the reason). It will not affect your future eligibility (as long as you didn't accept it then not do anything for it).
--You really are encouraged to be honest. Your job is not to sell the product, it is to spread the word and provide useful feedback. You will not become ineligible for future campaigns by providing negative feedback. The only personal tip I have is to do it in a tactful way. Instead of saying "I hated product Z and would never buy it!", you might find something you liked about it as well or something that they could change to make you like it. For example, "While I liked the size and shape of product Z, it's performance did not live up to my expectations because of ____" or "I did not like how product Z performed but I think that if they made the lid wider, it would have produced better results".
--Along with keeping up with your surveys, make sure that you link up your shopper reward cards for any grocery stores that they offer like Kroger, Ralph's, etc. It expands your chances of campaigns.