That is true - at least sometimes.
I am not sure but in terms of programming I guess there are not too many exotic modules and functions and if I remember rigth all you do is dotnet code, isn't it?
There is the Mono project which is available on both Mac an Linux and which could allow for compiling on both alternative platforms.
Maybe it is worth a try - if it works out of the box you will make quite a few people happy, if it doesn't, well, then let's leave everything like it is.
If you need volunteers for testing on either mac or Linux, drop me a line ;-)
Mike