Off topic: Please tell the client to fire the "IT guy" that suggested SharePoint. Now. Back to the original question, why are you trying to build a CMS from sc

Off topic: Please tell the client to fire the "IT guy" that suggested SharePoint. Now. Back to the original question, why are you trying to build a CMS from scratch? The project sounds like a customer facing marketing site. Is it giant brochure (web site), or does it actually do something (web app)? If it's a giant brochure and the client just needs to edit some pictures here and there, there are plenty of CMSes available on the market for Java and .NET. My company recently switched to WordPress for our marketing site because we realised we were wasting too much time reinventing the wheel in .NET for a mostly static marketing site. Now, if it's a web app, I would recommend going with whatever technology that talks to their back end the easiest, which in this case, sounds like the client is already using Java. I wouldn't want to try to get Mono to work on Linux, or switch to Windows hardware just to run a .NET web app, although I much prefer C# over Java.