ipad compared to an MBP is a toy
Kind of a useless statement, and without any context.
When you're talking business use, the main thing that matters is usefulness.
I don't buy a device because it is new or shiny, I buy it if it will help me do what I do better. That's how I make professional purchase decisions. Personally, I try to determine if it will help me enjoy my life more and if it fits in with the calculus of how I conduct my personal affairs.
The iPad is useful in ways that have nothing to do with processing power, operating system, etc. So if you use it as a "third device" and use it to it's strengths, it can dwarf the MBPRO. I know, I own both.
But if you look at just processing power and file structures and snow leopard and etc... then sure, the MBPRO is a desktop, something the iPad was never DESIGNED to be.
Based on usefulness, though, they both swing for the bleachers according to their designed uses.