yes. The more mAh's thelonger your battery will last.
I recently obtained 750mAh battery and tried it out on the E680 and it seems to work. However, will it damage the phone in the long run? What's the difference between 750mAh and 780mAh? Is it that 750mAh wont last as long?
yes. The more mAh's thelonger your battery will last.