In 1999 i quit my job in a mid west state and drove my car to dallas without any job offer because I believed that IT was not big in midwest. I chose Dallas over east or west coast because of its low living cost. the IT industry was very hot at the time so I believed it was not hard to find a job even with my minimal experience in the field. I switched from a science background to programming not long before that. I brought my PC and fax machine (at the time fax and paper mail was still widely used in job hunting). The third week I got an offer, only one. Then I moved my family to TX before starting the job. It was a memorable moment in my life.
I believe in today's IT market if you have some experience and do not need visa sponsership, it should be pretty safe to move to dallas. You may not get relocation package in the software field. Please plan two to three months for settling down and job hunting, but you may be lucky to land a job within a week, just like my wife who got an offer the first day moved to Dallas.
Also I was told by several recruiters that .Net market is much bigger than Java in Dallas. One recruiter said 8 out of 10, and another said at least 6 out 10 are in .Net, the rest are in Java and other fields like old asp vb, power builder, c++.
Good luck.