Well, I might be pessimistic, but after all Mono is now in the hands (however capable hands of its creator) of a start up company that AFAIK was still looking for additional investments.
>What makes you think Mono is uncertain?
>
>>With the future of Mono uncertain, I am not sure if .net complies with point 4 of the OP (if Mono was ever viable)
>>
>>4). Ability to compile on both Windows, Linux and possibly other mobile devices.
"The five senses obstruct or deform the apprehension of reality."
Jorge L. Borges?
"Premature optimization is the root of all evil in programming."
Donald Knuth, repeating C. A. R. Hoare
"To die for a religion is easier than to live it absolutely"
Jorge L. Borges