I have a 9300 and have been facing battery life problem from last 2 weeks. The life extends only for 6 hours tops with call usage of 15-30 mins and data usage of 2 hours. I am using the OS 6.0 bundle 2342.
I replaced my battery with the other 9300 i have. The battery was working fine in the 2nd 9300. And the problem persisted with the first one.
So clearly, the problem was with the OS.
I had my OS reinstalled to 6.0 bundle 1478 and then upgraded again to bundle 2342.
Problem still persists. The handset keeps working in the background all the time - the clock like thingie keeps on appearing.
P.S: I just realised that my data plan had unlimited video download last month and since then i have downloaded quite a few videos. Needless to say, few were unwanted too and it pains me now!