I recently got a Dell D610 laptop for the purpose of writing. This will actually serve two purposes; the first is that since it's a substantial investment, it's my commitment to writing. I'm actually going to do it. The second purpose is that since my writing is primarily going on here, on the blog, it will let me use the software and get a good feel for how it is to use it — it's often quite easy to tell software which the programmer has used from software which the programmer hasn't used.
Anyhow, I'd like to take this opportunity to recommend linux on the D610. It's not perfect, but the D610 is a nice laptop (comfortable, good performance, long battery life) and while it's not trivial to get linux up, it's actually not bad. The Sarge install was very straight forward (you need to use the 2.4 kernel for some reason). After that, download and compile your own 2.6 kernel (184.108.40.206 as of the writing of this post), patch it with this patch from this page, and then install the kernel. (I actually now find it easiest to build with "make-kpkg kernel_image" and then just dpkg -i the resulting deb. Note: you'll need to edit your grub config and set kopt_2_6=root=/dev/sdaN ro (Where N is your root partition), because in 2.6 SATA drives are scsi drives whereas in 2.4 they're IDE drives. (Incidentally, I just noticed that the guy who wrote that page helpfully provides his kernel image. I'll try to remember to do that too.)
I did have to go to debian unstable to get an xorg package, but after that it was easy. Just use the i810 driver and the 915resolution program (this is explained in the linked page) to enable 1400x1050 as a valid resolution and X works fine from that package. (Note: sometimes after suspending to ram the glidepoint gets jumpy, but so far it seems that suspending again will fix that eventually.)
the intel 2200 wifi card works great, of course; all you have to do is install the ieee80211 driver, then the driver and firmware (note: just unzip the firmware into /usr/lib/hotplug/firmware, and compile both drivers with "make && make install"). I prefer to use wpasupplicant as it's easier to configure preferences for, but waproamd is a bit easier to get going (they're the daemons which scan for available wifi and choose one).
Anyhow, there's not much point in me going on because this isn't detailed enough to be really useful nor high enough level to be interesting, but the long and short of it is that while it's a bunch of work to get a D610 working with linux, it's work and not hair-pulling. I suspect that this D610 will be a lot like the inspiron 9200 — a lot of work for a day or two, followed by a laptop which works well.
(Note: I'm really looking forward to the glorious days when it will be possible to make SATA hard drives spin down.)
Anyhow, if I get the time to write a step-by-step guide, I'll post update this post.