Is a 600cc motorcycle too much for a beginer?

The great thing about bikes is that they do not quickly depreciate in value. It is all based on the miles ridin'. Do yourself a favour and pick up a 2-3 year old 500cc bike to begin with. Yeah, its only 100cc less then the supersports, but have 50hp less than the CBR600's 130hp. You can still do a 1/4 mile in about 12 seconds on a 500cc, and will be able to sell it at the same price you picked it up for.