Good article in computer weekly on 2007.  Some interesting analyst quotes in there such as:

Clive Longbottom, service director at analyst firm Quocirca, said many organisations would find it worthwhile to upgrade their Micro­soft software across the board.

"There are a lot of changes coming through from Microsoft - Windows Server, Windows Desktop, Exchange, Live Communication Server, Sharepoint, SQL Server, Office - the list goes on. At some stage, the total offering makes sense. And if you are doing an infrastructure or total desktop upgrade, it makes sense to roll out Office at the same time," Longbottom said.

Dale Vile, research director at analyst firm Freeform Dynamics, said, "What Office 2007 brings may not be attractive to everyone, but there is a lot of potential business value in there. The only way you can make a judgment, and test the business case for early migration, is if you understand what is on offer and how it might fit with the way your business and end-user expectations are evolving.

You should revisit all of those grand plans you had for that enterprise portal project a few years ago that was never quite delivered, and look at applications that were destined to be embedded in that. The fact is that the centre of most people's desktop is Microsoft Office, not their web browser, so surfacing applications in Office fits much more naturally with user behaviour."