I don't think we'll see any new models until Mountain Lion ships. I'm surprised no one has mentioned the OS angle. Apple shipped the current mini after it shipped Lion.
To be fair, Apple has usually offered free OS upgrades for computer bought a couple of months before the new OS release.
Anyway OS release date will not influence hardware cycle for the simple reason that the OS could be delayed if some bugs couldn't be resolved in time, while setting up factories to manufacture hardware cost tons of cash so as soon as they are up (and getting obsolete by the minute) they have to produce what they were brought up for.
For my part I wish for a quad-core mini with discrete graphics (maybe Apple could produce something based on powerVR series6).
Easily upgradable internal storage would be a must (to put in a SSD). Then again with Apple buying a memory company from Israel it would be great to have macs use purely SSDs, maybe with mSATA format.
Now for my part there is some fear as for the future of mac when I looked at the macs trends and then the trends with mobile devices.
As you can see computers trends are barely registering when comparing with the iPhone and iPad... These generations (maybe the next 3) of classical computers might be our last (from Apple but seeing as other big names in the PC industry are moving away from home computers...).