Battery: I got 4 hours 41 mins on the X41 at level 6 brightness/Wi-Fi on/ Medium suage/ 8-cell battery. On the X1 I haven't done a proper test and i left the friggin charger back at home so i'll have to do that tomorrow.
HDD Noise: Definitely quiet with no unexpected noises, the loudest thing you'll get with the notebook is the sound of closing the lid...and even then there's rubber stoppers on the screen to pad this noise and cushion the contact between screen and keyboard area.
Line Out: No optical out, just regular stereo, I'm not an audiophile but I do listen to a lot of music and it's most certainly been fine for that...the sound quality will likely depend more on the headphones, try these Shure E3C Headphones
I'll definitely run benchmarks and include them in the full review, I've done some of these already but embarassingly the X1 has now run out of battery and I have no way to charge it at the current time [:I]
I haven't used VGA out on the X1, but I can't imagine that would be a problem, most notebooks can output by up to 1600 x 1200
Thanks a lot for the fast answer.
Your informations sound good.
yeah, that'S what i also know. Problem is, that the Notebooks are able to send 1600*1200 pixels - but often quality is not as good as it should be to work 8 or more hours a day at a LCD powered by such a signal. So it's important to have a good signal at VGA-out to be able to use the Notebook @home / @office 
maybe you can test that. I would be glad about that.
I love the X1 which is a rebadged samsung but hate the way dell deals. Seems like every day the price and price for options change on their website, nevermind the discount coupons. Today, for example, the want $199 to upgrade the 30gb drive to a 60gb drive, give me a break.
To me the X1 is the winner here, smaller with a better screen. Can't say how the 1.1 mhz will perform but the onlt think missing is the pcmcia slot which seems to be totally useless these days. Besides a network card (which is built into every laptop sold today)there is no need for pcmcia--bout a useful as a serial port these days. Having one, on the other hand, creates a soft spot where the keyboard will sage because of the open space created by the empty pcmcia slot.