Using open source products in such a customized way provides a great base for cloud efforts, while still preserving enough flexibility to change and grow later on.
Choose the Best Linux Server for Your Business
SJVN has a very helpful article here on ITworld for those you looking for the best Linux server for your business needs.
I think the single most important factor in choosing a Linux server is how experienced (or not) your IT staff already is with Linux. While Linux expertise is easier to find than it used to be, there's still nothing like enough Linux IT professionals out there.
When I went to OSCon, the major open-source convention, earlier this year in Portland OR, everyone, and I checked and it really was everyone (even some company named Microsoft), was looking to hire people with Linux and open-source experience.
In particular, employers are having trouble finding staffers with a few years of Linux experience under their belts. That is to say, exactly the employees you need to keep your Linux server trains running on schedule.
It doesn't surprise me that so many companies are looking for people with Linux experience. It just makes so much sense to use Linux whenever possible that it's totally understandable that experienced Linux folks are in high demand right now.
So if you have Linux experience, this is a great job market for you.