Nick,

Read your post and thought I'd send you some ideas that I've seen one of the local coffee shops here do. They're less than a mile from the closest Starbucks, but seem to do very well.

They offer free internet, Starbucks charges.
They have local bands play weekly.
They have a Myspace page with their calendar of upcoming music
They're coffee is great and somewhat cheaper than Starbucks.
The atmosphere is very warm and condusive to customers staying for a while.

Hope some of this helps. Many people are more apt to frequent local shops instead of the Starbucks giant. I think one important thing is to try and be as "grass-roots" as possible, if that makes sense.

Best of luck to you!
Roddy