I live in Houston and I like it. The inner loop is very gay friendly. Houston is the complete opposite of the old saying "It's a nice place to visit but I wouldn't want to live there". I can't see why people would come to Houston for touristy reasons, but I can tell you that I love the vibe of the city and the cost of living is great. There is also no state income tax and a reasonable propery tax (In Houston/H.I.S.D) The job market seems to be really good here as well.
There are tons of parks and outdoor activities available. Over the past 4 years that have more than doubled the amount of 20+ mile bike trails in the city.
There are tons of places to eat in just about every cuisine. There is more Tex-Mex than you can imagine here. Lot's of Chineese,Vietnamese, Mediteranian, and Indian as well. The only time you may have a problem is if you are a vegan, but there are even a few vegan places you can go you will just tire of them quickly.
Now if we could only get decent mass transportation in our city it would be even better. The rail system is in it's early stages and our busses aren't worth the extra effort.
The bar sceene isn't that great right now though. If that's big on your list then Houston probably isn't for you. There are tons of gay organizations of every type to join.
OMG the heat and humidity, that may be a deal breaker. It can get very hot and humid. It's good for the skin but sometimes it can feel like a sauna. The winters are really mild though and you can sometimes even get away with shorts during Christmas time.