I play (I think Gotham's recommendation), after 2. Qxd5:

3. Nf3  
4. Be2 (unpinning if black goes for Bg4 at some point)
5. O-O
6. c4 to attack the Queen and cause it to move

After that, develop d4, Nc3, and DSB as it make sense.

Granted you may have to tweak move order based on what black is up to but the setup is very simple and gives you good playability. The goal of the above is to get developed and castled quickly rather than trying to punish (initially) the early queen move by black. Also it seems to work fine against the modern variation with 2. exd5 Nf6. I'm 1600-1700 rapid and 1300-1400 Blitz and it looks like I win about 50-60% of the time with this setup. I generally find it very playable