I moved to Houston from Chicago but so far have stuck with United/Star for most of my international trips. I fly regularly to Asia (mostly Hong Kong) and London. Continental offers no direct flights from Houston to Hong Kong (I'd have to change in Newark), so connecting in Chicago/San Francisco where United has hubs is quicker. Continental does have direct flights to London but in my experience the inconvenience of flying to Gatwick is about the same as transferring in D.C. or Chicago on United and continuing on to Heathrow. With United you get E+, which is vastly superior to Continental's economy offering, and a generous upgrade policy. You also get access to all Star Alliances clubs at the premier executive/elite level while flying in any cabin. With Sky Team, you have to be top tier to have access to their clubs (and they have fewer clubs than Star). If buying full-fare or discounted business tickets, though, I have found Continental to often offer a better price. If you will be doing a lot of flying within North America, Continental is the way to go. In my case, though, I lucked out since the routes I regularly fly out of Houston are either served by United or Air Canada making it possible to stick with Star.