I have mixed feelings about this. The game is promising, I prefer this to japanese RPGs, the dog and the coop play all have a lot of potential. The technical part of the graphics looks impressive, and all my friends tell me Fable 1 was a very good game already.
I wouldn't call it a very good game, it was merely decent. Lots of the stuff promised by Molyneux somehow was absent in the final game. Moreover, it wasn't exactly a RPG, it was more of an action-adventure, TBH and it had its fair share of flaws and imbalances (e.g. mana shield + big ass sword was ridiculously powerful, I didn't even get scratched at all, against the bosses). The quests were nearly always linear and offered no choice to the player (no moral dilemmas, etc.) [in fact, thinking back the only choice offered was what happened after the last boss* of the original game].
The were some novelties: Your character aging & receiving scars, picking up random women [though receiving scars didn't really affect your chances of picking up women if you were somewhat famous], but all of them had zero impact on the gameplay. They were more of gimmick than a part of the gameplay.
Ok that sound awfully negative, so let me reiterate: it wasn't a bad game, just not an RPG. I had fun playing it (otherwise I wouldn't have bothered to finish it or the expansion), but I wouldn't call it "very good".
* not counting the expansion "The Lost Chapters"