Also, easy to take around- useful if you are working with someone else. The downside is the obsolescence aspect.
Try not to get too hung up on that - whatever you buy will still be able to do what it can do now in 10 years! It's a vicious circle!! The Mac I do most of my recording on is 6 years old - still does enough tracks and runs the latest version of Logic, and touch wood gives very little trouble. I could upgrade it but if it ain't broke don't fix it!!
Breaking can be a problem! The G3 PowerBook I got in 1999 finally cr@pped out a year or so ago; the G4 iBook that replaced it is still trucking, but I worry about it. Mind you, a less nomadic lifestyle than mine that involves stationary desktop machines will result in less wear and tear! ;)
Plausible multitrack recording software is
cheap. Macs basically come with GarageBand (which is sort of "Logic Lite") for free, and that will get you a
long way. If GB gained the ability to specify tempo and key changes within a song (rather useful!), it would be pretty killer. My PC using friends swear by N-Track Studio, which is shareware, the cheapo version of Cubase (whichever two letter designation it has) is easily found in Mac and PC versions.
There are lots of decent USB or Firewire audio interfaces these days. I decided I didn't need Firewire throughput since I'm not recording more than a track or so at a time, though Firewire would be useful for multitracking a band all playing simultaneously. However, I'm tempted to replace my current USB interface with one of the new Line6 Toneports, which is just another USB audio interfaces but with the Gearbox guitar/bass amp-modelling software thrown in. Guitar and line level inputs, even phantom power for mics on the higher end model -- all at a reasonable price, really. I might replace my Tascam with it, just to get the guitar/bass amp models.
I'm of two minds regarding the obselescence issue. If I buy standalone hardware (drum machine, POD thing, even a guitar!), it will likely keep doing what it says on the tin, if no more, forever as long as I don't trash it. If I buy something software-based, it's more likely to be upgradeable -- but also more likely to stop working altogether if my old machine dies and has to be replaced by a new machine or OS that doesn't support this particular software. This is my main dillemna regarding amp modellers: the PODs stand alone, but the guitar model has no bass amps and vice versa, while Gearbox is realtively cheaper but is just software tied to the computer. Have to think more about it ....
I'm still trying to settle on a decentish condenser mic for vocals and acoustic instruments. I've been thinking mostly about the Rode NT1A and AKG C3000B, but haven't reached a decision. Obviously, if you're mic'ing amps, an SM57 is indispensible :)