If I remember correctly, there's already a pretty decent thread about this.
Just like in residency, try and find out as much as you can about the practice prior to the interview. As mentioned above, if you have an interview they usually need you and will try and sell you on the job rather than vice-versa. Big things to keep in mind is that $/hr =/= salary. Benefits (especially malpractice insurance with guaranteed tail) can add up and actually have a higher total compensation at times. Do you get paid salary, straight hourly, hourly with productibity, or fee-for-service?If it's a partnership, what's the buy-in and what percentage of docs make partner? How many hours per month are you expected to work? It's more tiring being an attending then a resident, and you probably want to be working fewer hours than you do now.
In terms of the hospital, what specialties are available and when? What services are difficult to admit/consult? How are transfers (both to and from) managed? Do you have responsibility for handling codes upstairs (suprisingly common in small hospitals)?
I'm sure there are many other factors, but those come immediately to mind.
