I agree with the MacBook Pro assessment. I bought a MacBook, and it is serviceable (I upgraded it to 3GB of RAM) but at times the on-board graphics show it's lack of strength and some things slow down a bit (this is an older 2.0GHz C2D MacBook with the GMA950, although the newer X3100 isn't much better).
Again, it's not too bad, but it depends on what type of "design" you are going to be doing as well. If money isn't a concern, then get a MBP with 4GB RAM - you won't be sorry.
I probably should have gotten a MBP, but I'm not really pressed to get one as I am going to get a Mac Pro soon and do all my work on it and use the laptop as the portable it was really meant to be.