I've never seen a job opening for an Azure developer. Sure there might be ASP work, but you almost certainly won't be working on cloud or mobile apps. It's nearly impossible to build a large-scale cloud architecture using Microsoft technology, and Microsoft Windows phone represents such a small portion of the market that it is inconsequential to ignore it completely. These are very strong reasons to avoid Microsoft technologies when choosing something to learn regardless of how employable ASP developers are at the moment.