Go i5 or i7 and fill it with ram running Windows 7 64 bit.
Rock solid and I have yet to have a virus or bug attack my win 7 system :-)
Get one with a USB3 port, you can edit raw HDV from a eternal USB3 drive no probs.
On my $1200 AUD ASUS i5 here, I can edit raw Canon 7D mov files in realtime even.
However with any PC you need to take time to fine tune it and decrap all the rubbish software they put on them. 
All good points in this post. My minimum requirements for a new Windows laptop are:
- i5 or i7
- 4gb DDR3 Ram
- 320gb HD. I don't believe you need huge hard drives in a laptop; it's better to have several USB HD's to offload your photos/videos to. For that matter, I would rather have a 128gb SSD in the notebook since that makes your laptop FLY and then just carry a 500gb USB drive.
- USB3 for fast reads, but not many notebooks have it yet.
- If you are a video guy then get an external blu-ray burner, it's not necessary to have it in your notebook; just makes it more expensive and if you have multiple PC's the external is the way to go.
- HDMI out - almost all of them have this now.
The HP mentioned above is a good choice, but I prefer the new 14" HP Envy series - $1050 with i5 processor. The "feel" of this notebook is very mac-like. Best touchpad on a Win7 notebook I've seen.
Oh, and the previous poster mentioned you need to spend some time De-Crapifying your PC -- There is an excellent program which is actually called "PC Decrapifier". Free download.
http://www.pcdecrapifier.com/
Also check out the Asus notebooks, they have a very nice feature set. I particularly like the Bamboo series, around $1100 with an i5.
If you need an ultralight notebook for traveling, check out the Toshiba Portege r700 series; 3.2 pounds, i5, 4gb ram, DVD burner - $1299. http://laptops.toshiba.com/laptops/portege/R700/R700-S1321 It's missing usb 3.0, but it has everything else. Super light and Toshiba is well known to be one of the most reliable brands out there - they have a 3 year limited warranty, most laptops are just 1 year.
As you already know, Sony Vaio's are also great machines, but a little pricier. I think I like their keyboards the best. If you could swing it, their Vaio "Z" series is just fantastic, but that ups the ante to about $1700 for an i5 box.