After doing some research, this is what I found:

According to their About us part of their web site and an article frrom last March, Skybus intends to put in 150 seats into the Airbus 319's they just bought. If both sources are accurate, you can expect an easyJet type of seat pitch (29"). Another thing to consider is that, according to Wikipedia, Skybus intends to be "modeled after the European airline Ryanair". The aforementioned news article also mentions that a former top official from Ryanair, Charlie Clifton, has been working with the management of Skybus while it was raising start-up capital. As you can imagine, pilots are tickled pink at the prospect of flying for them. As far as I can tell, Skybus still hasn't decided where they will fly from Columbus, but as of last March, they have ruled out Las Vegas, Chicago and Tampa, Fla.

Awkward post script: after digging a little bit deeper, I came across this photo of a Skybus jet from airliners.net. I noticed that it only has one over-wing emergency exit. Don't you need more than that to carry 150 people on a 319, like easyjet does (easyJet has 156 seats in their 319's)? My google-fu is weak in this regard, but I remember reading that the maximum capacity of 319's and 737's with only one over wing exit is 137 or something in the US. Can anyone confirm?

Other sources I came across while researching this article:

Airline bulliten
Emerging Airlines Monitor