The R707 Owners Manual and Camera Dock Manual can be downloaded here:

http://h10025.www1.hp.com/ewfrf/wc/manualCategory?product=371583&lang=en&cc=us&lc=en&dlc=en&

You cannot copy the photos from internal memory to external flash drive with USB cable without using PC.
You can however transfer those photos to a SD card that is inserted into the camera. (page 121 of owners manual).

The maximum supported SD card size is not shown in the owners manual. But HP sells the 512MB SD card for the R707. I have seen 1 gig SD cards advertised by others.

HP states the photos per charge is from 115 to 260 with an average of 200. (page 167 of Owners Manual).

The Dock is only REQUIRED if you want to connect the camera to a television set, and show photos on the TV set. Otherwise it provides an easier way to connect your camera to a computer or a HP printer. It also can charge batteries.

Opinions on the Camera:
It is a fairly new camera so I only found one Owners Opinion, but it is worth reading.
Go To:
http://www.dpreview.com/reviews/read_opinion_text.asp?prodkey=hp_r707&opinion=22152

There is a full professional review at:
http://www.dpreview.com/reviews/hpr707/

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