My brand new ZS10 lasted about two weeks...before I dropped it in salt water. It was only under for around 3-4 seconds...but that's all it took. The repairman told me that he can fix it, but it will cost almost as much as a new camera and he can't guarantee that the camera will run properly (it was a "maybe...maybe not...can't say until after the repairs are made...").
In comparison to my ZS7, I liked the additional zoom and the fact that it doesn't go out of focus like the ZS7 every time you zoom in/out on distant shots. Having said that - 10X is about as far as you can go IMO and still get a steady hand held shot. Even at 10X it can be a challenge with such a small camera. If you've got a tripod - you're golden on the close-up zooms though.
One thing I really didn't like about the ZS10 is how poorly it functions in low light. Basically, I found that unless you had lots of bright light, the video came out dark - even with the manual exposure set to a high setting. The ZS7 isn't significantly better - but in experience, it does better in low light. So in a lot of small clubs where the lighting isn't all that bright - it's tough to get a nice shot with the ZS10.
And also - not only do I not like the ZS10's 30 minute limit, you never know how much time you have left on a card until you have less than 30 minutes on the last clip. With the ZS7, you always know how much time you have left.