I've been on the "good problem" side of scalability on the MS platform. It can scale if you can scale your wallet. Monthly bills of ~$54K hosted at Rackspace be

I've been on the "good problem" side of scalability on the MS platform. It can scale if you can scale your wallet. Monthly bills of ~$54K hosted at Rackspace became monthly bills of ~$18K after a rewrite using Java, JRuby, HBase over C# and SQL Server. We tried Mono. It was a headache to convert (2010, 2011).