I upgraded from a Rebel XT to the 60D and then added the 70-200 f2.8L IS II. My main need was figure skating, grade school sports, and indoor events. From the XT, this was a huge improvement.
Shortly afterward, I added a 17-55 f2.8 IS. It wasn't long when I realized that the XT was a poor second camera, then I heard the calling of a refurbished 7D direct from Canon. The 7D proved to be a great improvement with more challenging sports action.
First, the difference for me wasn't really with the 8 fps. I rely more on timing of the first shot then may burst a second or third one. But, the biggest issue was with tracking erratic movement such as with figure skating. My guess is that the 60D had an in-focus success rate of about 80% where the 7D was at least 90%.
But, perhaps the biggest problem was that I didn't fully understand the predictive nature of the AI Servo mode. It isn't completely live focus, but rather it records movement to predict where the subject will be when the shutter is actually tripped. So, it works great tracking a subject that moves in a straight line. But, it can be off when the subject changes direction. The 7D can usually keep up, but the 60D lags behind when tracking the change in direction. It's sometimes best to momentarily lift your finger off the focus lock when the subject changes direction to force the camera start its calculations all over.
Another issue that you can run into is with burst mode or "near" burst mode. The 60D can only burst a few RAW images before filling the buffer. Part of this is due to the slower SD cards. It does a better job with smaller JPGs. Still, for me, this wasn't a huge problem.
That's the negative and is most noticeable with challenging sports action.
I still find the 60D to be a great camera and the articulating screen was quite handy for both creative shots and candids. Today, I mostly shoot with two 5D3's, but I kept the 60D (and the 7D). My wife kids now use these. On occasion, I'll grab the 60D and 17-55 or the 35 f2 IS for a lightweight grab shot camera -- especially for times when I don't want to carry 5 grand worth of gear for more casual shots.
For crop bodies, if lots of sports was my main need, I'd be tempted to look for a refurb 7D. But, for a more general purpose camera that can handle sports, the 60D is a great choice. Keep in mind, it's only when compared to the 7D that 60D falls short in the sports department.