i bought the x10
I got it because i had front row tickets to see roger waters and they would not allow dslr camera in only point and shoots so i figured i needed the best low light capabilities i could get in a point and shoot and the x10 performs well up to 3200 iso (it will go higher but i avoid it) and the lens base apertures is f2 to f2.8 on the 4x zoom. build is really really nice and functionally everything works really well I noticed the other day in manual focus mode it has a depth of field indicator on the live view screen as you focus, Nifty! also i've used ex580 flashes off camera with it using ebay poverty wizards and it will sync to 1/800 sec
as to be expected the smaller sensor doesnt yield the sort of narrow DoF that you get from a 5Dmk2 at f2 but its great for low light shooting battery life that I am seeing seems to be around double what the documentation says, hell I got over 1000 shots off 1 battery and they rate it at 400!
Also a nice accessory i have picked up for it is thishttp://www.ebay.com.au/itm/Lowepro-DMC-Z-Slim-Memory-Card-Wallet-Holder-Accessory-SD-CF-Batteries-/120912267727?pt=AU_Cameras_Photographic_Accessories&hash=item1c26eec9cf
you can fit the spare batteries and memory cards in it and they are well protected
I havent encountered the white orb issue that people have complained about yet so cant comment on that
great little camera
about my only gripe is i would like to have some basic data in the VF like exposure scale aperture shutter speed and ISO, but the auto iso is so good you can use the camera in manual all the time and let auto iso adjust your exposure
AF is a little sluggish though however it will shoot 10fps and another neat trick is when you are reviewing shots it groups all bursts so you see the first one for each group then the next group and you cna then just go into each group to view each individual shot.
also video looks to be exceptionally clean i havent used it much but it is lacking an external mic port