We have a team on vs 2005. We want to upgrade to vs 2008 but want to do it incrementally. If we have a few folks on the team upgrade to 2008 (still targetting the 2.0 framework) while others working on the same solutions stay on vs 2005, would this cause any issues . 

* Do solution or project files change due to this?
* Are there any backward compatibility issues to deal with or other conflicts that is going to force a big bang upgrade for the team?