But it hides that good looking machine.
What good looking machine? When the Mac Pro finally appeared at my local Apple Store, I went down to check it out. The color of black wasn't black black but silverly black, the case was larger than I expected, and it didn't look as good when Apple first announced the Mac Pro last year. The only bright spot was a security lock connector.
If I were to get a Mac Pro, shoving it into a 4U case seems ideal.