Few commercial projects will open source their code, unless they already have reasons to believe that they can't be usurped for one reason or another.
The flip side of this is that for business/enterprise
software, there is very little risk in just making
your code open source and then selling a
commercialversion.
What if your competitor takes your open source code, adds a little bit of value, and sells cheaper than your commercial version? Or, if there's some clever (algorithmic) thing you are doing, what if he uses your ideas to better compete with you? Design. ($25 of stock icons doubled my sales back
in the day. Most OSS projects do not have anyone
who would care enough to secure the equivalent.)
I'd love to hear more about this (before and after pictures, etc). What are those stock icons? Did you have no icons before?