I did a little bit more investigation after filing bug 111359 (https://bugs.launchpad.net/ubuntu-website/+bug/111359), and realized that the wiki situation is a bit weirder than I originally realized. In addition to the slowness that I reported in the previous bug, it looks like there are actually two separate wikis that my Launchpad account creates accounts on. There is http://help.ubuntu.com/community and there is http://wiki.ubuntu.com. If I make changes to my user preferences in one of these wikis it does not carry over to the other wiki. This is confusing, especially since searching for pages from wiki.ubuntu.com will lead me to pages on the help.ubuntu.com wiki, where I can edit pages but my user preferences are not in effect.
I spent a little bit of time trying to figure out what was going on, and it seems like a number of internal links in wiki.ubuntu.com actually redirect to pages on help.ubuntu.com/community. This leads me to assume that wiki.ubuntu.com is the old wiki, and help.ubuntu.com/community is the new wiki for end users. If this is the case, and at some point everything will be under help.ubuntu.com, then it's probably OK for now that my user preferences are not the same for the two wikis. However, if the plan is to keep these two wikis around as distinct wikis, then I think it makes sense if user account information is kept in one place only, so that if I make changes to my wiki account on one wiki those changes carry over to the other wiki as well.
Thanks for your bug.
Yes, the plan is for both wikis to be distinct - they serve different functions. We're working on improving the way that users understand this distinction in this specification - https:/ /wiki.ubuntu. com/ImproveWebs iteStructure
It's a good idea to keep the user preferences single for them both so I'll confirm the bug.