Recently I had the pleasure (or displeasure) of moving some existing asp.net sites to a Content Management System (CMS). The sites relied heavily on some ASP.NET modules for cookie tracking and some other things, so we needed to have an ASP.NET CMS so we could keep this logic. After a bit of searching around I narrowed the scope to two open source products: N2CMS and Cuyahoga.
I actually found Cuyahoga first and had thought that it would be perfect for us. However once I starting having a good look a couple of issues became deal breakers. The first issue was the Cuyahoga uses the Web Project model, which means that the site is complied into assemblies. So if we needed to make a small change to the site we would need to deploy an updated assembly. A rather small issues you might say, but for our needs it's actually a big deal. The other issue was the lack of versioning, hopefully it will get added in a later release.
After it became apparent that Cuyahoga wasn't going to work for us the way we were hoping, I jumped on codeplex to see what else was out there. It wasn't long and I found N2CMS, this looked from the outset to be a better run project. I really liked the declarative approach to creating templates as well.
So I rolled out N2CMS, its worked out OK, a few little things annoy me, but I think they would be a common problem in most low end CMS applications. For example I have some functionality in some user controls, I would love the CMS to allow me to just drop them into a page, rather than creating a template.