Sorry, I cannot recommend Toshiba, in fact, it is one of the few I would definitely not own. My former company (who has a JV with a Toshiba company) actually now has a corporate policy of "no more toshiba." They sell well, but somehow just don't hold up, and repair costs are astonomical.
My beef with Sony, is that they are really a media company, and their big focus is preventing people from using music / movies in any "non standard" way. I am not a pirate, but I do feel I should be able to record the music and movies I own on my laptop, so I can watch them when I travel. (which is a lot) Sony does not agree, so they go to some length to prevent this in their products.
I am a big fan of AMD processors. Their mobile processor actually has variable speed, so it speeds up and slows down automatically to deal with the processor load, vs go / stop of Intel (maybe this has changed). Think about your car, do you floor it then let off the gas, or run variable speed ?
Both of my kids ended up with HP with AMD for college - very happy.
What do I carry - an IBM. I like the little pointer stick and I just hate the little mouse pad. (this is a very personal preference, as everyone else in my family likes the pad).
If you are going to be on the road a lot, IBMs are really tough. If it is mostly for home use, most can work.
I agree with the comments on Centrino, that is just Intel hype. If you want WiFi / 802.11, there are much better add on cards for range and speed than the Intel option.