Same amazing battery life here.

Luca, Snoshrk, your machines (hardware or software) have something wrong. Even if streaming uses logically much more power thant reading from SD card, you should'nt get so poor results !

As usual in this case try :
0/ charge fully your battery
1/ deactivate ALL your applets/taskbar applets
2/ go to in flight mode
3/ close ALL your running programs
4/ play a long video from your SD card

How long does it play now ?