I think we have a well kept secret - Microsoft Dynamics CRM is not actually a CRM system (well - technically it is but stay with me). Microsoft Dynamics CRM could also be called the even more catchy
"Microsofts rich platform for building a lot of brand new applications in a lot less time and code than if you just fired up Visual Studio and started from scratch"
(which can be abbreviated to Microsof RPFBALOBNAIALLTACTIYJFUVSASFS - which I think is pretty catchy!)
It turns out that Microsoft CRM allows you to easily extend the database schema with additional fields and entities, modify the workflows, amend the screens, generate new screens from scratch, customise security etc.
Want some proof? Well, check out this session at MIX which shows real applications built on top of Microsoft CRM or just download the PPTX.
If you are an ISV you should be interested...