It's all about availability of performance (ie. wider, stickier) tires for a particualr wheel size. For example, the BMW 2002 tii came stock with 165/80R13 H (130mph) rated tires. Most people have gone to 14" or 15" wheels on their 2002s because there are more high performance tire choices.
If you read the
Tire Availability thread, you'll see that there are 205mm tires available for 15", 16" and 17" wheels ... assuming that all these wheels are wide enough to handle this tire size. Remember though, as the wheel size and tire width increase, the sidewall height decreases and the ride gets rougher.
After tire availability it's a matter of what you think looks good on the car.