I noted a few things about the article. Before I begin, though, it is well written and definitely seems to be a topic many would be able to use. Thanks!

• Your instructions for making the /share not mount automatically at boot time does work but completely obviates the benefits of determining the uid/gid stuff ahead of time. Putting "noauto" among the options lets it reside in fstab -- benefiting from pre-configuration -- while allowing it to be mounted when needed.

  Going one step further would be to add "user" to the options as well. This does imply a few changes to "defaults" (user implies nodev, noexec, nosuid), and in fact "defaults" isn't needed. The resulting union of defaults with noauto and user gives "rw,user,noauto,async". In a simple dual-boot computer where the user typically has full access, this simplifies everything ("mount /share" as the user).

  The now changed /etc/fstab entry would look something like this (sorry about formatting): "/dev/hda4 /share vfat rw,uid=1000,gid=1000,noauto,user,async 0 0".

  There are a few times (e.g. multi-OS projects) when the user will need exec (or perhaps even suid). Those are the exception and, in my opinion, it's better (and more secure) to make the user want to include those if needed. (That's why, if I understand it correctly, "user" implies "nodev,noexec,nosuid".)

  There are definitely other ways to automate this (perhaps using autofs or something similar), but for single-user systems, those solutions are rarely that helpful.

• There is a an extra space in your modified linux profiles.ini for firefox (immediately before "z9qffpsf.default"). I'd assume that most users would be savvy enough to not include that verbatim.
• On my system (gentoo 2005.0) with thunderbird-1.5.0.2-r1, it is stored under ~/.thunderbird vice ~/.mozilla-thunderbird. I really wish they had standardized this to be under ~/.mozilla/thunderbird right next to ~/.mozilla/firefox, but symlinks are easy :-).
• One more thought on the use of another partition. If the windows installation for some reason is already installed on a FAT32 filesystem, it'd be considerably easier in the configuration stage to keep the windows configuration unchanged and point the linux-based firefox/thunderbird configurations to /win/Docu.../ instead.

  There is one subtle drawback to this. I'm a fan of keeping all user documents (and email and ...) in a centralized and easily found location such as this extra partition. By sticking with the windows location, you are not gaining that advantage. That's minor and more of a personal technique, however.

  This can possibly bite somebody when they perform an upgrade to windows, using NTFS instead, and they think to themselves "Oh, I don't need to back that up, it's on the linux side as well." (Contrived, perhaps, but feasible I guess.)

Thanks for the article.

-bill