This is true, mostly. However, the FPU is not the most stressed part of the processor just because you're playing an MPEG and an MP3 in the background. The whole processor is dedicated to running one program at a time, in most cases, and the computers that can make exceptions to that rule (Cray MTAs, etc) don't get programmed in VB.
Also, all floats are signed.

That said, for well-pipelined processors like the PowerPC, doing integer stuff in the FPU can be a 1337 assembler trick. More pipelines create more parallelism.