Certified addict here. I had the original Sims and all the expansions. Got Sims 2 the day it came out. Sold all my originals because they didn't compare. Have every single expansion pack on 2 as well, always get them the day they come out.

Already pre-ordered Sims 3. I have 2 computers now thank goodness (yay Christmas), so Sims 2 staying on the desktop, Sims 3 going on the laptop. I pre-ordered the special edition.
Oh and, I've played all the Sims games on PS2, Wii, DS, etc. plus MySims. None of them even come close to comparing with the PC version. It's a world all its own. There are no "goals" per se like the game console versions, so it's just free will and alot more options, add ons, etc.
When I play I'm in another world, been known to do it straight for 2 days (well used to in college anyways). Now I try to limit it to once a week or so...but when I do it it's for at least 8-12 hours at a time. I'm a true blue fan, been there since the beginning. On the little trivia game during the load screen on Sims 2 I know all the answers. Sad, isn't it?