If you want...when i took it like 07/08..i DID NOT lol...because incase i didnt do so well, i didnt want my application to be tossed in some of the schools i applied to.
Im glad i didnt, i took it in the beginning of my junior year...and when i took it again beginning of my senior year i probably went up 150+ points.
If i were you right now, i probably wouldnt...i believe after 08...you can choose to send whatever SAT scores you want now (my year colleges saw all attempts) so if you dont think you will do well, wait, do well then send the one you want them to see.
You can send them now if you want. I wouldn't think it would make a difference if they see your scores and you didn't do so well because it seems expected to take the test more than once. I don't know for sure though. I think you do have to pay though if you want to send these scores later and have not taken the test again. Of course though, you'll probably want to take the test again and you can send the results then for free.
It probably doesn't really matter if you send them now or not, since schools usually just take the best score or superscore, but personally I just sent my best score later on when I actually started applying to schools. Good luck.