I've been working with .Net since it first came out and have done my best to use the latest and greatest things from Redmond. That being said, I've been working for the past year in the Python/Unix/Web world. In order to keep myself relevant in the MS world, I've been working part-time on a WPF project but I do not know how much longer that work will continue.

So my question is: If I were to move totally to the Unix/Python/Web world, how long could I stay there before it starts getting hard to get another MS job? I am trying not to burn bridges in my career as I've found MS jobs pay better and tend to be more plentiful.

PS: I like my Python job since it is something new and I get to work from home. It has provided a different view on coding that I've found useful.

EDIT: I was out of the MS market for 12 months before attempting to get another MS job. No-one said "Gee you've been gone a while" but I did get a conspicuous lack of responses to job applications. My feeling is that the head-hunters do not bother to look beyond your last job. In the end, I got employment via my own network rather than the pimps. So, to answer my question: "not long, especially if you trust your career to head hunters."