Macs are quite capable, and I used one for almost a year in a previous job. That said, I wouldn't get one again - I found the UI increasing irritating as time went on, and got annoyed by the number of things (focus follows mouse being the prime example) that I took for granted in Linux-land, but came under the heading of "Shareware. Pay after 30 days." on the Mac.

A Mac might suit you, and they do suit lots of Perl hackers, but it didn't suit me. I've had 18 months of recovery and am quite happy sticking to Linux (and I've just bought myself a new laptop from Novatech and slapped Fedora on it - very nice, and much better for my bank balance then anything from Apple ;).