Mac Fanboy ahead! Longtime Linux/FreeBSD user, switched to Mac on my main machine about 3 years ago. Fair warning.
1) Well, it Depends on what you want to do. Right now, I own a Powerbook 800Mhz, and 1.2Ghz or 1.4 Ghz in the mini would be a nice speed bump for me. But honestly, my current machine still meets my needs. I'm probably going to upgrade when the new Intel laptops come out. Mainly I use my machine for web browsing, email, personal programming projects and the occasional game. Apache, postgres, turbogears all work fine for development purposes. No way are you going to get decent performance with demanding games. World of Warcraft runs on my machine just fine. Just guessing, if you aren't that demanding on your machine (graphics, games, data processing), then a mini should suit you just fine for 2 years, IMHO. 2) Again, without more info, its kind of hard to say. 3) Well, now that's just crazy talk. 4) See #1 and #2. 5) I LOVE being able to pay for software. Note I said "being able". Using Fink (google if your not familiar with it) and the builtin X server, you can pretty much run any random free (U|L)inux app on your machine. So really, you aren't going to be leaving anything behind in that regards. In addition, you can now use commercial apps if you would like. Things like Photoshop Elements (or the real deal, if thats your thing), Macromedia software, Microsoft Office, or Apple's software. You don't need to use it, but it is really nice to sometimes splurge for an app that there was no way you were going to run on FreeBSD. If you could list more of your requirements for what you will be using the computer for, people can probably give better responses.
