Migrating from MSVC 6.0 to Studio 2005?

greywar asks: "While the preferred method would be simply use Linux, unfortunately my company is using Microsoft Visual Studio 6.0 with C++. I have been asked to recomend if we should upgrade to the new upcoming visual studio 2005. Has anyone got any real life experience with moving a project of about 220,000 lines of code, 60,000 lines of comments from the old MSVC to the new Studio 2005 which is currently in Beta? What benefits are there, and what things do we lose? What problems will occur?"