I think I'm more likely to hear bad stories rather than good stories about cars on the internet, 'cos that's what the intenet is for. To moan about things!
I take it the Series 1 & 2 variations are just change in trim bits and bobs?
Minor differences between Series 1 and 2, not a big deal really.
Differences are S2 got Blue&Me (bluetooth) standard on all models, they dropped the 1.2 engine, added the GP trim (sporting look with the standard 1.4 engine), changed the headlights slightly, put the new red FIAT badge on instead of the blue one.
TBH I was gonna get one, I've driven a 1.2, 1.4, 1.4 16v and 1.4 120bhp Tjet, so all the petrol Grande's they do. The 1.4 16v was a bit pointless (named Starjet), not really any faster than the standard 1.4. The 1.2 is nice round town but struggles above about 80mph, the standard 1.4 is just like the 1.2 but faster and better at higher speeds. The 1.4 Tjet (120bhp) is nice for a midly warm hatch but drinks fuel like anything.
Personally I'd look for one of the following (depending on your budget and how new you can get):
56/07 plate Series 1 1.2 Grande Punto in Eleganza/Dynamic trim
Late 08/58 plate Series 2 1.4 Grande Punto in GP trim
Girlfriend test drove one and loved it as well, don't buy new, get an 18 month old one and pick up a bargin.
Personally I'd go for the older 1.2, just because the Series 2 are still losing a lot of their value, a 56 plate nice example with loads of mod cons could be picked up for about £5k now.