T3i, T4i or T3? as my first DSLR

I agree with Brandon. If you can check out the cameras in a store, that may help you make a decision. I recommend the T3 or T3i because you can put the money you save toward a nice lens or a Speedlite (there's not much you can do with the little on-camera flash). You'll also need memory cards, a UV filter for your lens and a bag to hold everything in.

Canon T4i is an improvement over T3i. It takes all the strengths of T3i & addresses all its shortcomings.

T4i has latest DIGIC 5 processor while T3i has DIGIC 4

T4i has better & faster AF in live view mode & has decent AF in video whereas T3i has none.

T4i corrects for Chromatic aberration for jpgs in the camera

T4i has higher ISO capabilities

T4i has touch-screen

T3i is cheaper & has great image quality. It is definitely not a slouch compared to T4i. Just check your budget. For a beginner, it is more than sufficient. even if you plan on to become serious, this will be sufficient for years to come. If you are planning to go pro then Canon 650D will be a better investment.

While you are at it check Nikon D5100 as well. As per DXOmark & some reviewers, it has arguably superior image quality to Canon 600D & is in the same price range which is far below Canon 650D. In real life shots, I found that difference were minimal & were noticeable only when either high ISO of 6400 & above was in play or in high contrast situations where Canon 600D was prone to purple fringing which to be honest isn't even noticeable 95% of the times. 

If you have small to medium hands, then you will probably love Nikon D5100 ergonomics. I have bigger hands & Nikon felt really uncomfortable but that's me. I bought Canon 600D because I felt image quality was comparable & just loved the feel of the camera.

I recommend that you go to your friendly neighborhood store & have a play with them. You will be surprised how your opinion changes when you feel the product & use it. All the research & reviews go out of the window at that instant.

T4i has much better overall AF, better Video AF and live view AF using LCD screen than T3i.

It also has Canon's latest Digic 5 processor that gives T4i better high ISO and image processing capabilities than T3i. It doesn't mean T3i's high ISO capability is mediocre, T4i is just better.

T4i will not replace T3i but will be higher up model and T2i will be discontinued.

T4i has touchscreen controls; some may find this feature very useful, others may not.

As for the sensor, it is essentially the same sensor as T3i, BUT it does perform somewhat better than T3i under certain circumstances due to Digic 5 processor.

If video and touchscreen is not that important to you, I would recommend T3i and use the difference to invest in quality lenses.

If you don't think you'll be doing any video, then you'll definitely save cash by going with the T3i. Most of the T4i's enhancements are better-suited for video, it seems. One thing it does have, though, is a touch screen, which is a first for Canon DSLRs. If you get a chance, try them in person before you buy. Either, really, would be great.

- Brandon

Nikon's offer significantly better image quality for less. Try the 3100 or 3200 if the D5100 is out of your price range.