the 24-105 is great on FF. If you can rent first give it a try and also the new tamron 24-70 2.8. The tamron is shorter, a bit more expensive (not canon 24-70ii territory), but gives you f2.8. see what fits with what you want to shoot.
funny you ask this as I have been walking around a lot with my 70-200 and not bothering to take any other lens with me and using my iphone as my wide angle camera. Seems to work for me, IQ is on par with just about any other mid range PS out there plus it has the advantage of being very light and something Id take with me anyway. It also is the best PS on the market for taking the photograph, doing some quick pp through snapseed and off to my facebook or flickr accounts. But if that doesn't work for you I'd invest in the 17-55 f2.8 IS over any of the wide to normal primes especially on APS C. Its way more flexible and you don't lose much if anything in the IQ department. My 17-55 was glued to my 7d.
If you're taking photos with facebook or flickr as the only location of the end-product, you don't need a DSLR.
One more opinion to muddy the water.
You seem to like portraits (based on your photo stream). The good news then, is that you can invest in lenses that will work on either full frame or crop without having to decide between the two just yet.
There is nothing in your pictures that will be improved by going full frame, but a lot that will be improved by getting a longer lens. Choices would be: 85mm; 100mm, 135mm or 70-200mm. All will give you a little more reach which will flatter your subjects and create greater separation between them and the background. Even on a crop sensor, all of these lenses are very usable for portraits.
Also, consider investing in a strobe. With the T3i you can remotely fire an off-camera flash. You'd be amazed at how much you can do and learn with a single off-camera flash and an umbrella.
Cameras are short-term investments, lenses are long-term investments. Invest in a lens or two now, and when you feel you've outgrown the camera, then start shopping.
My real question was if canon is going to be better when they come out with 18nm or if they will just be on pair with Nikon.
This was with my 50d and 15-85 at iso200 at f8 and 1/8000. I love my mkiii but sometimes miss the old guy.....