I apologize for not making myself clear. I meant to say that there isn't the depth of software availability - not that the existing software lacks depth in features.
For instance, there are several solid NLE programs for PC, but I've only heard of one for the Mac. The software tools that are available for the PC, far outnumber those for the Mac and hardware is much, much cheaper.
I've got three solid programs for audio tweaking, more programs for music loops, some for keying (Ultra 2 & After Effects), etc.
In software development, which I still do a bit of, you must have a PC if you're going to develop for the mainstream user.
In a business environment, Microsoft Office rules. You gotta have Word, Excel, PowerPoint, Visual Basic, Access and in a corporate environment, perhaps FoxPro.