You only need 45 points for the $5 giftcard, and you can typically earn between 1-5 points a day just by searching the internet. Basically I log on once a day, search for a few things, and earn some points. Best of all is that they have a referral program so you can match the earnings of your friends. So I went to bed with 40 points and woke up this morning with 45.
It's definitely a legit site, and it's fun to earn gift cards for doing something that I would be doing anyway.