Let me preface by saying I am no pro, nor do I want to make money at this. I am a novice / hobbiest. A self proclaimed dork. The technology and science Behind photography interest me as much, if not more, than the art. From that standing take my viewpoint with a grain of salt:
starting out with your T3i will give you the right challenge level to learn how everything works, but in order to advance to a career level you will need to advance with gear more suited a professional. Something to access and make changes to aspects of your camera quickly, preferably with only your thumb, not needing to delv into a menu.
I own a 60d. I can control focus point, drive mode, ap, shutter speed, iso, and many other things without my eye leaving the viewfinder. This makes sports photography easier ( I only shoot hockey and very beginner level). I would argue the 7d will prepare you better for a 5d than the 60d. And it is more geared to where you want to be. Don't rush though. Learn what you can on your t3i. Get some fast lenses (2.8 70-200, 400, heck maybe even a 24-70. If you can get close enough)
those lenses will still be good for your 5d when you get it. I went Sigma to save money, and I didn't need the ruggedness. Most will argue the L glass would be the better by, but as I mentioned I'm no pro. Hope I helped. Sorry so wordy