1) Houses... Houses everywhere
The suburbs is nothing but an endless sea of look-alike cookie cutter homes. The houses look interesting
2) Lack of decent entertainment
Adding to point #1, there's hardly anything going on in the suburbs. Occasionally, you might see a Wal-Mart or a McDonalds, but that's about it in terms of entertainment. I don't think anyone goes to those places on a daily basis.
3) There's no one around
You hardly see anyone walking around the neighborhood. I'm not counting people who goes on the driveway to get in their cars, doing yardwork, or checking the mail. You can go for days and not see a single soul anywhere. It feels like a ghost town.
4) Hard to meet new people and make friends.
In the suburbs, most people are married and have families. They tend to have a close social circle and prefer not to interact with anyone outside their clique. Plus they have busy lives which consists of working, raising children and watching T.V. Just like with point #3, there's no one around which makes it hard to meet new people and make friends.
5) Lack of dating options.
Most of the women in the suburbs are married middle age women or retired grandmas collecting social security. There's hardly any young single women in my age bracket (in the 18-30 range). They don't hang out in the burbs. They hang out in the Urban core or around colleges.
6) Too far from everything.
I live in an area with a population between 200k to 300k. It takes me about 20 minutes to get to the Downtown area where the young singles hang out. Once in a while I like to drive but I prefer to walk. Plus, parking is hard to find. The nazis that run the city overcharges you for parking, or you end up with an expensive parking ticket.
7) Too quiet.
The suburbs are too quiet. When I hear a car pass by or a dog that suddenly barks, it feels like a bomb went off in the middle of the night. Anyone who's been in the military probably knows what I'm talking about.

The suburbs are great if you're married and have children. But for me I'm not that impressed with the suburbs. I'd rather live in the city, or only within a few blocks. I recommend young single guys who wants an active dating and social life to invest in a condo in the city rather than a luxury home in the burbs.