Nothing - but only had it one day!
Great little car - exactly what I was hoping it would be.
Roomy inside, albeit with a bit of a shortage of storage space for CDs etc - which is fair enough given it is so small!
Great quality finishing throughout.
One of the first things I noticed is how quiet it is in the cabin, even doing 100kph on the freeway - amazing. Don't have to have the stereo cranked up to max to drown out the world outside, unlike my previous car (Toyota Corolla).
Fuel consumption is showing 7.4 L/100kms, but I expect this to improve as it gets driven and worn in over the next few hundred Kms.
The dealer included seat covers which I wasn't expecting - pleased with that - though they are a rather shocking pale blue, which is not a choice I'd have made. Still, with kids it is a useful add-on and free, so can't complain too much.
Seats are little on the firm side, but again it may soften up a bit with time.
Handling is good - tight and responsive with a pleasant "nippiness" about it. I am used to bigger cars so this is a good change.
I also checked out other possible buys, such as the VW Polo (nasty, retro/70's, cheap, plasticy inside - very disappointing!), Toyota Yaris (weird central console for the dials, general cheap feeling about the finishing inside - and absolutely tiny inside, especially in the rear) and am sure that the Jazz was the best of the class by a fair degree.
All in all, I am very pleased with all aspects of it so far.
I have had the same model Jazz for 8 months travelling 15,000km and agree it is a great car. I had a Jazz previously which remained trouble free for 50,000km, this new one (made in Thailand) has had problems with trim and dash rattles from the start. Disappointing in such a well designed and innovative car.