Now that I have a little more time...
I truly believe that you'll find Mac OS X and a nice Macintosh or two to be your ideal platform (or as close as you'll get this decade).
I myself am a programmer, and that's what I love most. But there are hundreds of other little things I love too, and the Mac lets me do them with the least hassle. Mac OS X is, I believe, one of the best programming environments available. You have X11 available and most UNIX software will compile pretty effortlessly on OS X (in fact, most of it is already compiled and packaged). Apple's own development tools are quite capable (such as being able to build Aqua UI's on top of Java apps - I don't know if you've done much Java programming, but GUI design in Java SUCKS. This takes the suck away). Perl (as well as most scripting interpreters) are available. So you can program for the Aqua interface, for Qt/GTK, command-line only... it's a beautiful thing.
It also gives you a pretty wide application choice. I break it down into four groups: Apple, ISV's, UNIX and Major Software Companies.
Apple's software is spectacular. If you do any video editing, you'll be amazed with iMovie, just because it's so effortless. I was showing iMovie to my dad last night, and in two minutes I had imported that fun Crab-vs-Pipe video, added a title, added a transition between two scenes (that looked quite professional), made the second scene look like it was taken from aged film and added a soundtrack. iTunes will also become your choice MP3 jukebox software because it's so simple yet so powerful. You'll appreciate Safari, Apple's new browser (that's still in beta). iPhoto absolutely rules for sorting your digicam pictures (or any digital images you have), as well as small touchups (like removing an unsightly pimple in three seconds flat or getting rid of red-eye even quicker). iCal has some ways to go, but it's actually quite good for calendaring and scheduling (if you need that sort of thing, which I do). And guess what - I haven't mentioned even a quarter of all that's available from Apple, most of it absolutely free to you (or included in the cost of your machine, depending on how you look at it).
ISV's put out stuff like the weather program I'm now using (called Meteorologist), nice FTP clients (I recently bought Fetch), Konfabulator, Mozilla, etc. I include shareware and freeware here. Stuff that's written specifically for Mac OS X. Believe it or not, there is a <b>lot</b> of high quality software available here. I've mentioned a few of the really good ones, but there's lots that I haven't. You'll love the software put out by guys like you and me.
The UNIX apps are the ones that are generally written for Linux and then ported to Mac OS X an hour after the source is released. They run great on OS X because of the magic of rootless X servers. Check out this
screenshot from my PowerBook. That's Linux's own Xchat running there, recompiled for OS X and installed in about two minutes via
fink. I use Apple's distribution of X11, but you can use XDarwin if you prefer. There are thousands of UNIX apps available for OS X. This is really nice if you can't find, for example, a decent IRC client (I'm waiting, shareware people - though I bought Ircle).
And lastly, the platform is supported by a lot of major software developers. Microsoft, Adobe, Macromedia, Aspyr (for games)... just about everyone. If you've been using only Windows, this is no big thing. But for Linux geeks like myself, this is great. Linux sucked hardcore in this regard. And even Windows has something to learn - the Mac versions of the software are arguably better than their Windows counterparts. I kid you not, Microsoft has touted Office X as their best version ever. Microsoft is saying "yeah, if you want the best environment to use Office in, buy a Mac".
It doesn't hurt that OS X has an assload of great stuff built in, either. Here's a good link to click:
http://www.apple.com/macosx/
Read about all the technologies in Mac OS X (especially Quartz Extreme - I can't get over how cool it is).
I'm just getting started! I'mma go to bed now, but I'll add more tomorrow and this weekend. Start reading on
http://www.apple.com though - you'll find lots of good information.