I'm definitely game for a Texas meet. Austin would seem the logical "in the middle" destination. One possibility I haven't heard mentioned is Hippie Hollow. While not everybody might be interested in having the first ever Live Nude Empeg Meeting

, they do have a nice parking lot and a pleasant lake. Alternatively, we could meet up at the Salt Lick, even if it is out in the middle of nowhere. Mmm... barbeque....
Personally, I'm travelling on business for almost the entire month of May (*sigh*), but most of June and July work just fine for me. I've driven to Austin plenty of times. I usually budget 2.5 - 3 hours to get there from Houston, mostly depending on traffic on the end-points rather than in the middle. Given the heat, we might want to save the obligatory "playing with each other's car stereos" session until after sundown.