For some time now, the Gemini image has been available for the 7025 (see
http://i-have-a-dreambox.com/ for obtaining these images you need to register on that site.. then in the database section you can download the images).
It generally repackages CVS releases but adds some more nice features. Unfortunately the one killer feature that has not yet made it to 7025 is the web interface.. there is a web server plugin but its only for hosting pages on the box as an actual server.. it has nothing to do with setting timer events or changing channel etc from the web.
But stability wise, the improvements are quite good.
As for upgrading the box.. see
http://www.dream-multimedia-tv.de/dm7025/index_eng.php
There are 2 methods.. using a DHCP network or via serial cable with dreamup. I'm not sure if the flash wizard methods are working yet.. in any event, I find the DHCP method real easy and fast.. you power cycle the box, holding the ch-down button and the LCD screen will shortly display the boxes DHCP address... then a standard browser can display a firmware upload page at that address where you can select the image to upload from your client PC and upload and install from there.
Before I upgrade, I telnet to the box and "cp -r /etc/enigma2 /hdd" to backup settings so that after the upgrade and reboot (which defaults to DHCP) I can login and restore my settings.
Hope this gives you some guidance.