As a newcomer to the Dynamics world 18 months ago, I was at once impressed and bewildered by what I could do as a developer with these technologies. I took a special interest in CRM, and read all about its extensibility model, envisioning all kinds of scenarios for CRM callouts and workflows in the apps of the ISVs I work with.
It turned out that I was being a bit too glib in my pronouncements though, as when I tried to write my first callout using Visual Studio 2005 I quickly ran amok of the requirement to target .NET 1.1. I had to hunt down a custom project template to get the targeting to work properly - you can find it here if you need it.
Well, I'm glad to report that those issues will soon be a dim memory with the forthcoming Titan release of Dynamics CRM. For one thing, callouts have been redubbed plugins, and for another thing, they work just fine with Visual Studio 2005 and the current .NET Framework.
One interesting point here though is the addition of support for asynchronous plugin event processing. This is good news for anyone needing to carry out a potentially long-running process in response to a CRM event firing. Ugly hacks like my roll-your-own queuing are no longer necessary - the server just handles it for you.
Even better than that, you'll also be able to attach workflows built on the Windows Workflow Foundation to Titan events, indicating further uptake of .NET technologies within Microsoft's server products. This, of course, opens up all kinds of integration scenarios (my favorite) in a much more straightforward way than we had previously.