Before anyone goes out and buys any kind of bike, they should first take a close look at themselves and determine what kind of riding they are going to be doing. Ask yourself these kinds of questions:
What kind of riding will I be doing? Commuting to school/work/whereever? Or just for fun in the twisties? Or out for long roadtrips? Or track racing? Or stunting? Or just getting around the town/campus/city/whatever?
Will I be carrying a passenger on the pillion? Will I be transporting books/laptop/groceries - Do you want/need a Givi-case or sattlebags?
How much riding experience do I have?
How much weight can I handle?
How much can I afford to spend for gas/tires/maintenance/insurance?
... there are alot more I could add to this list.
If I am going to be using the bike for commuting on the highway and will be carrying a backpack, I don't necessarily want a Gixxer or SV650S (sorry SuzukiGirl!). The tank-humper position is not good for being seen, and not good with extra weight on your back. And like I've said before - a GIVI has no business on the back of a Gixxer - it ruins the look of the bike.
If I am going to use the bike for long rides (hundreds of miles per day) and my name is not Dale

, then I probably don't want a Gixxer either.
The rider position of the Gixxer (and SV650S) is a racing position - the intention is to go as fast as possible, with less focus on visibility or comfort. The Bandit, Katana, SV650 (without the "S") and other "street" bikes offer a more upright position, which IMHO is more comfortable and more visible (the cages see you, and you see over them).
A cruiser is great for 100s of miles straight ahead, but less fun in the twisties, and no fun whatsoever in slow-speed manoevers like tight parking lots, etc.
If I want to stunt, then even 500ccm is too much. If I was into that, I would get a 250ccm rat-bike. They are light and cheap. If I'm practicing wheelies and stoppies, I don't really want 500+ lbs of bike ... and I don't need 100+ horsepower, with $300 for a set of tires.
And if you want a radio, heated seat, cruise control and a reverse gear, go get a Gold Wing. Or just buy a new Beetle convertable and leave the 2-wheeling to us.
Just my $0.02 ...