I created a patch to close it. I would post a warning using a sitenotice and some central discussion page at the wiki that it is going to be closed and after some time (a month or so) after the notice the patch would be merged&deployed and the wiki will be closed. Is it acceptable for you?
Sitenotice added. Suggest we close on the week of 10 April. There's no need to wait a month IMHO, and that way we will avoid the planned code-freezes, etc. If you think we need more time I don't object though.