ok... let me share with you how long mine can last. basically i did a full charge some where around 3AM. then it stay put at standby mode. start making and receiving calls around 11AM. did some SMS, 5 mins of mapking. total at least 20 mins of calls and around 25 SMS. oh yeah, not to mention 5 mins of games. and the conclusion is, till now 5.00AM my battery is showing me 50%.

what i did was disable auto adjust backlight. set both on external power and on battery power to 3rd line. i believe it still can last me another 12 hours.

the ce-star came with HTC CD is causing this issue. i also had this problem and not sure what went wrong and did a hard reset, then only found out that it was ce-star causing this T_T. btw, there is a newer version of ce-star which u can download from htc club. specifically for diamond. so far i have no issue with weather update. currently running on 1.93 ROM