I've used wine on-and-off for the last 3 years. I am very impressed that it can do so much, but every time I start using wine thinking this is the time it will be great, I usually become disappointed when application X doesn't work.
Don't get me wrong, the work that wine developers is great... but usefulness is usually measured by that one application that you can't get to work rather than the 10 that do. I know that I can get Office 2000 to install and I think I had Office XP for a short time but in each instance I spent 30-50 minutes getting it set up, finding out that Windows MAPI (Proprietary Exchange protocol) doesn't work. Two years ago, our organization upgraded to Exchange 2003 and left the web application available for internal users. Now I have Evolution's exchange-connector (Thank's Novell) that can access my mailbox and OpenOffice 2.0 that can read and write most Microsoft Word documents (I'm batting 100% with Word and Excel but I'm not a heavy document user. Before OpenOffice 2.0, I would get the text but no formating so I am leery of suggesting OpenOffice as a fully integrated MS Office package.)
WineTools was/is a great package to automatically get Internet Explorer installed on your Linux machine. However, I never felt it was fully supported and winetools would use different conventions than winecfg. I would usually end up with a working application and 5 different ~/c.2006.backup folders for each application I wanted to customize wine.
I'm so excited to see where WineDoors goes, that I am going to see if I can contribute something, maybe the deb package, maybe documentation, but my real goal is to see if I can learn how to program.