GP9 Overview

Based on the GP 9 overview, these are the compelling reasons for US to upgrade from 8.0 to 9.0:

• Available enhanced Audit Trails (extra cost)
• Available electronic sign off (extra cost)
• New Payables check batch window and streamlined payables processing (free)
• Home page, connection to Outlook is nice.
• Installation improvements
• Mass deployment (Outlook, SMS, or Group Policy)
• New set up checklist
• New GP webservice for Integration (Developer Toolkit)

Some other things I like but which don't specifically apply to TransitTV are:

• Extender (Extra cost)

Your mileage may vary. I've talked to a number of people on 7.5 and an upgrade to 9.0 will give them a lot of 8.0's benefits as well ,such as undoing JE's.
The Developer Toolkit for GP is a great idea. The ability to use VS2005 to extend GP and avoid Dexterity has the ability to be huge. Anything that opens up GP to more developers is a good thing.