I personally find long-term use of X annoying and clunky, so the Mac interface wins out there. (Please don't try to convince me I'm wrong about X. If you don't have a problem with it, that's cool.)
If you're just doing basic run-of-the-mill web development, and it looks like you are, then a MBP will work just fine. If you're in Vim and Bash all day long, there isn't really much for you to learn. Some things are a little quirky, off the top of my head I think Apache2 is installed in a weird location, and command line app X may not be installed by default, but it's probably no more obscure than switching to a BSD or Solaris.
If you're just doing basic run-of-the-mill web development, and it looks like you are, then a MBP will work just fine. If you're in Vim and Bash all day long, there isn't really much for you to learn. Some things are a little quirky, off the top of my head I think Apache2 is installed in a weird location, and command line app X may not be installed by default, but it's probably no more obscure than switching to a BSD or Solaris.