Taking quality photos at Concerts, thats also compact

I think the S100 is great for concert photography even when cropping it is still good. If your happy to use and process RAW that will probably help as well.

If you really need more zoom it may be worth trying one of the HX series Sony cameras although I've not put them through their paces.

Here are some shots from the S100 recently

https://www.facebook.com/media/set/?set=a.521992827257.14480.222600292&type=3

I HAD the same problem, and I did a lot of research and I can't recommend enough the Canon Powershot S series. 

I absolutely love my Canon S-90. I got it for exactly the same reason. I love night and low-light photography. I take it with me everywhere I go. And I have gotten many many beautiful shots with it's manual controls and pretty well thought out auto-settings. 

My one complaint is that I can't shoot in RAW on all auto settings. I find myself using the manual mode fairly often for this reason. 

If i had 10 votes I would vote 10 times for the Canon Powershot/S90/S95/S100. Here's some shots I took with my S90. 

cm7a69c  at tinyurl.com

I think the Canon S100, S95 or SX240 HS are your best options. 

The S100 doesnt have even close to 10x zoom - maybe the Olympus SZ31 would have what you're after but still be pockatable:

oly_sz31mr at www.dpreview.com

HTH