Eigenvector wrote:
This might sound like a dumb question, but is there a proper orientation for
an outlet?

Snip

Not really.

Does the orientation matter so far as code is concerned?

No. NEC 2005 is totally noncommital about it. In fact, GFI outlets have
the 'test' and 'rest' buttons readable in either verticle position.
However, Traister's 'Commercial Electrical Wiring' p.240 shows ground
hole up in vertical orientation and neutral (longer) slot up for
horizontal mounting as preferred practice.

Flip a coin and then just be consistant with the job as a whole.

Joe