Nevertheless I've also done some other things, the most important being to re-install VS2008...
I did this for 2 reasons:
a) Unity 3 and VS2010 have some co-existence problems. In fact, I couldn't manage to directly open a C# file in VS2010 from within Unity 3. The damn thing couldn't locate some kind of proxy to open VS2010 and opened the files in Unitron (the Unity script editor).
VS2010 also tried to re-import the project files more often than it was necessary.
b) one of my former customers requested me to do some work for him and *that* requires VS2008...
Now Unity opens the files/project in VS2008 without a problem and the customer's work can begin next week...
But before I'll have a trip to Paris for another customer. Sometimes it pays to speak more than one language ;) I'm no native french speaker but since my wife doesn't speak any other language than french, a costumer of mine figured out that I could help them during an on-site meeting.
This means, that I'll not be back here before Saturday or Sunday...
Have fun...