Remember the beginning of Season Two, when you got paired up against Plats in your placement games and got trashed? I certainly do, and I don't want to repeat it. I'm going to wait until half the population returns to their original Elo, and wait for the new items and jungle changes to set in before I get on the Ranked bandwagon. I'd like to discuss why you should consider doing the same.
If you have a naturally high Elo, go ahead and have at it. You can climb back to where you belong in a matter of a few games. Could you have a string of bad luck and drop to 1k Elo? Sure, but the Elo gains are going to stay around +/- 20-30 for a very long time this season, until the system gains confidence in your ability to play. You'll climb back up soon enough.
If your Elo was very low last season (bronze or even pre-bronze,) I suggest you wait it out. You're struggling with the basic game mechanics as it is, and some big changes are about to be thrown in your face like a bittersweet pie. I'd suggest reading a few guides and playing in normals in the meantime. Visit http://www.solomid.net/forums/index.php?/topic/31280-official-elo-hell-advice-thread/ for more help with the game mechanics, champions, choosing your role, and anything else you need help with.
Soon, new items will make some older champions more viable, or new champions simply OP. Your normal "go to" item build will change, some minor, and some drastically. (I for one see Mercurial Scimitar being used on every ADC ever.) It will take time for you to test all of these and see which ones you like the most, if you haven't already done so on PBE. Prices have changed as well, making champions like Riven (whom you usually just bought a Ninja Tabi, a Chain Vest, then called it a day against,) keep their power a little longer in the lane phase.
Don't be too rash. Wait it out, try the new jungle and items, and see where your favorite champions stand after the changes. Once you've settled into the new Summoner's Rift, go ahead and claim your Elo!
See you on the Field of Justice!