Well it still works, sort of. As long as you don't get any ambitious ideas about getting it to sleep (the easy) bit and then wake up (the hard bit.) I've been watching this one carefully and about once a week I open the lid to be greeted by a black screen. Nothing brings it back except a power cycle. One of these was in a meeting when I was depending on this thing to deliver a presentation. Dell have clearly been trying to fix this - the BIOS has been through ELEVEN versions and the video drivers have been updated.
It generally wakes up during the night to do backups and various other Vista things. It mostly goes back to sleep again, but not always.
Docking and undocking is mostly works, but sometimes it takes minutes to sort itself out after being docked and every now and then it moans that the docking station power adapter is the wrong sort. Sometime it "goes weird" (Vista technical term) and needs a reboot after a dock or undock.
The wireless connects like lightning but every now and then hangs so that you have to turn it off and off again using the switch. It then remains unreliable until a reboot (oh, so many reboots.)
Having said that, when it's up and running (which is most of the time) it's powerful and well built. The trouble is, it has Vista on it!
To be fair, I don't think these problems are specific to the new Dell E-Series, it's just that Vista can't handle all this sleeping and waking stuff and finds docking all rather stressful.
I rather envy my wife's MacBook. Open the lid and it wakes - instantly and every time. Close the lid and it sleeps - always. Updates come rarely and always work (and it's all nicely automated - no emails telling you to download things.) The MacBook never "goes funny", needing a reboot and it's not traumatised by having things plugged into it!