Battery life was pleasantly surprising on the Samsung i8910 HD, lasting over a day on super-heavy usage and nearly two in general day to day use (which consisted of a lot of video watching). The quoted standby time of up to 450hrs is probably a little bit of an over-estimate, but Samsung has been canny with the size of the device and pushed a 1500mAh battery under the hood, which would explain the extended battery life.
The organiser, which consists of a calendar, note taker (which sadly has no handwriting recognition as far as we could see) a converter and a smart card reader for picking up business card details, is stocked enough to be useful without turning the phone into a business handset.
The business card reader was the most disappointing application of the bunch, as despite it managing to find the outlines of a card no problem, it couldn't read any information whatsoever, no matter how hard we tried. We don't think we'd be using this feature that often, but it's so cool we really wanted it to work.
The calendar is pretty standard fare, with the haptic feedback working nicely to let you know when you've hit a day, and an array of meeting or reminder buttons placed along the bottom so you don't have to go trudging through menus make the experience a lot nicer. In the future, you have to feel that this application will only become truly useful should more mobile phones start syncing with the likes of Google easily (although Exchange is supported).