Surveys are worth it sometimes, in my opinion offers are better!
Here's the difference:
Regular offers, unless they can be completed every 24 hrs, can only be completed once per the terms of service and eventually you will run out of these. The daily surveys and the daily tasks can be completed every 24 hours and so you will not have to worry about a lack of supply. That's how you can reach the $15 threshold in offers that you need in order to cash out. The only other offers that can be repeated daily are the DCE and PTC offers. Referrals are great (if you can get them) but since they count as bonuses, not offers, they don't help toward that $15 in offers you need in order to cash out.
Another thing. It's always a good idea to check for new offers every day once you've exhausted all of the regular ones you are interested in. Surfing the forum to see which offers, if any, new offers have been noticed and are currently being recommended by other members is a good way to stay on top of this.
I'm a big fan of the daily surveys because by attempting them all every day has allowed me to cash out 12 consecutive times so far. There is a learning curve involved and some patience and persistence certainly help. That said, I usually manage to qualify and get credited for one daily survey almost every day without spending too much time doing it or getting overly frustrated when I'm not successful. Case in point:
GlobalTestMarket Survey - 04/18/2012 2012-04-18 $0.50 ApprovedThat makes today a good day on FC with a total haul of $.73 so far for about an hour of my time. I did the DCE and PTC for $.17 and completed my searches for the $.05 in rewards. There was also a video for $.01. I'll check back for more videos periodically throughout the day. This is my post worth $.10 toward the $3/mo forum posting bonus and that's a wrap.