I went from a Dell to a sony...happy with my decision, but by no means disliked the Dell. Dell made a really solid machine, well built, good materials, great customer service, great sound, cool running, and a totally sub-par screen. I was tired of the exchange game. Although in Dell's favor, getting an exchange out of them is pretty easy.
Had been thinking about an AR...so was able to make a trade for one. My first laptop was a Sony that I managed to flog for a solid 4 1/2 years with the only problems being a hard drive replacement at 2 years, and cracked LCD hinges after about 3 1/2..which I didn't think was bad. My impressions of the Sony after a couple months is that the build quality is definitely not as good as the Dell. The Dell just had a very solid feeling, everything fit well, nothing loose, no creaks, very rigid. But, the build quality on the Sony is not bad either, I would say acceptable, just feels a little more delicate. The screen on the Sony, while not being as high in resolution as the Dell, is worlds better than the Dell screen in terms of image quality, and evenness in lighting, no comparison. It's far brighter as well. The Dell was hard to see in some situations during the day with the backlight all the way up, while the Sony is almost blinding at night on max....this means you can see the screen in the daytime no matter what, which I like. The keyboard on the Sony is also far better than the ultra stiff, loud "clicky" keys on the Dell. I have yet to deal with Sony's customer support other than to ask a warranty related question (about transfers) which was answered quickly, and the rep was pretty nice. Overall though, the Sony just has a really alluring character (sounds lame, yea) that makes me want to polish it like a fine automobile.

heh
Not sure if you're thinking about an SZ, which seems to be the most popular Sony model these days. If it were between an SZ and an M1210, I know I would take the SZ anyday. The SZ is a super slick machine, and the dual graphics idea is great. (if only they could combine the 7900GTX with the Intel GMA 950

) M1210 has it's good points, but I can't get past the fact that it looks as though it was designed by the same team that designed those Emerson clock radios in the 80s. I know some people love the appearance though, i guess it's subjective.
Edit: OH! And the Dell forum here at notebookforums is MUCH MUCH more exciting than the Sony forum. That's what I miss most about the Dell. SolApathy..good to see someone from the other area.