I've been a member of Taxi for 1½ year. I posted about 20 songs the first year without getting a single forward.
The cretique was very helpfull and let me on to another trail - Instrumentals. The last 6 month I've had 6 forwards and I've learned that my Danish accent and my singing skills are simply not good enough to compete with the many exelent tallents using Taxi. I'm yet to experience the big company contacting me and it may never happen, but one thing is for sure: Taxi can be exactly what you need if you want to be a better writer/composer/singer/enginer/musician. But you need to face the fact, that no matter how good you think you are, there are others that does it better than you and untill you are at least as good as those others, you wont have a chance to do well in the business.
Another thing I want to point out is the Taxi Tv on youstream.com broadcasting every monday for one hour. Some of those broadcasts contains golden info for plain folks with a disire to improve needed skills.

http://www.sonicbids.com/kendamkier
http://www.myspace.com/damkier
http://www.songramp.com/homepage.php?userid=20896
http://members.soundclick.com/kendamkier
http://www.youtube.com/user/kendamkier