We've just got one of these at work, you can use it like an external drive, so if you drag the wav file on to your desk top it should work with most good DAW software.
Ableton live is great for creating live loops ect, but Cubase is a better all rounder.
I've also used the h4 files on both Protools and Logic 8 (which is fantastic, so much better than prev versions).
BTW I think the H4 would be a must have peice of gear if you could use the internal stereo mic + the 2 line inputs at the same time to record to 4 tracks, imagine what you could do at live gigs!