We're historically a microsoft shop but recently (in the last 18 months or so) have started running linux backend servers for many of our services running on EC2. If I wanted to be buzzword compliant I'm sure I could come up with some string of cloud nonsense to describe it.
We have something that looks kinda like Hadoop crossed with an app server that we can deploy components in.
I'd be happier with a solid final version of Mono.Simd rather than slavishly filling in any missing parts of older .net.