Well, the new WP Super Cache is available now.
This release adds experimental object cache support. Don’t go looking for it unless you have an external object cache already. It won’t show up. I recommend using the Memcached object cache.
Some of the other major changes include more translations: Chinese (Pseric), Ukranian (Vitaly) and Japanese (Tai). The Italian and Japanese translations have since been updated but not included in 0.9.9. You can grab them from the languages directory if you don’t want to wait until the next release.
If you have WordPress Mobile Edition installed the plugin will grab the list of mobile user agents from that and warn if your .htaccess is outdated.
And, a small but significant change is that the PHP cache loader will use the static “super” cache if necessary. This might happen if your rewrite rules aren’t working properly and not serving cache files. At least your anonymous visitors will see some sort of cached file. Use the debugging system built into the plugin to determine where the cache comes from.
See the changelog for the complete list of changes.