Will my target audience reject a .net solution?
SwellJoe: I don't think it will be dramatically more likely than losing customers because you've written it in a language other than .net and the shop is all-Windows (which is a pretty high percentage of small/medium businesses, as they haven't yet reached the point where the cost of Windows server solutions becomes a big number).We occasionally lose customers because we don't have a Windows version, and our products are smack dab in the middle of Linux' stronghold (web servers for shared hosting).I do think it worth noting that Fog Creek builds their apps in a meta-language that compiles to PHP and .net, for this very reason.  Given that they are historically a heavily Windows software oriented shop, I think it's worth considering why they would go to so much trouble, and do something so batshit crazy as to write a whole new language, just so they could reach those non-Windows deployments.In other words, I don't know.  Launch with what you know and what you can build quickly.  When you have customers, and are talking to new customers, you'll find out quickly whether you made the wrong decision...and it will be in time for a course correction.  Rewriting in a new language three months in is a 1-2 month job.  It'd be a setback, but not crippling...and getting started right away is better than letting analysis paralysis set in.