Roughly in order of precedence (the closer to the front of the file,
the more likely it'll be done before next release):

Change logging infrastructure to use the new logging module in 2.3.

Update the database infrastructure to allow other RDBMSes.

Improved (and perhaps integrated Services and Enforcer plugins.



To be done as soon as someone with the necessary expertise is found to
help us:

Finish the Infobot plugin.