Thank you for your reply with these useful links. I have just checked mine and it seems that i am on version 11.0.008. Actually so for i haven't encountered any bugs which other members have been mentioning, so i wonder whether i should update the firmware or not?
As the article states a firmware update will not only fix various issues, it will also make your device run smoother, less glitchier and in some occasions even add new software (e.g. v20 adds a dictonary application). Bottomline its your choice