<p>About a half dozen times now, I’ve been doing a regular chore in Visual Studio – either running a unit test or simply compiling, updating something from SVN or whatever, and visual studio just disappears… it shuts down and goes away instantly… it is fine when I restart it, and I don’t see the problem again for a while… it keeps happening, and for random reasons… has anyone else experienced this?</p>

<p>One thought is that i'm using AnkhSVN, but if you've had this problem and don't experience this, please let me know.</p>

All of the devs on my team see this problem quite often. It isn't AnkhSVN because we don't use it. I believe it is C++ intellisense, but that is just a feeling. Sometimes it happens when we are not doing anything. We will go for coffee, come back and it is just gone.
It never happens to me on smaller projects, but happens frequently on our large (several million lines, dozens of projects) solution with a mix of unmanaged C++, managed C++ and C#.
We have seen it less frequently since upgrading to SP1.