Well, I got mine from Amazon UK. It installed about 50% from the DVD. It then wanted to launch Steam (which I already had) and then took about 30 mins downloading the other 50% (I have 1Mb/sec d/l speeds).
My game plays via steam and I am having no problems whatsoever.
Am really liking it - was really lookign forward to a decent openign video/introduction with "space, the final frontier", etc and am a bit disappointed. Still, am liking the music and being able to alk around the bridge so far.