I second what most people have said:

• the growth -- I've lived in other parts of the state/country briefly that felt like nothing ever happened (west Texas), or that the best times were in the past (Illinois circa Great Recession); Dallas-area has been exploding my whole life and seems in no danger of slowing down. The increased traffic and all these out-of-state license plates do get old, but it's never dull around here.
• diversity -- since the late 90s especially, the Asian communities here have exploded. Food has gotten better, and it just feels to me, though I could totally be wrong, that a lot of the endemic casual racism I grew up w/ around here has abated significantly... Dallas used to be a really fucking racist place, and I think it's less so now
• weather -- if you can tolerate the summer, the few weeks we get of fall and spring are pretty nice, and the winter ain't bad. Summer nights when the sun goes down are spectacular if you can tolerate a bit of sweat.
• economy -- if you're in tech, anyway, there's a good chance you'll never struggle to find employment.

Dallas is a pretty lame place to visit but a great place to live.... My family has been in this area since Peter's colony times, so I'm sort of blessed/cursed to be here forever -- but all in all the ancestors picked a great place!