Cydia 1.1.23 includes some features
Support Package Downgrades
All too often, I release a new package, and find out during the first few hours after release that there was a serious regression :(. Even if I pull the new version, users who upgraded do not have a way to easily downgrade.
Now, not only will Cydia allow you to downgrade to the "current" version, but it also allows downgrading to any previous version that is available on the repository. Going forward, I will leave previous versions online for some time while users are able to sort out issues.
Find Extensions for Applications
This feature was directly inspired by UnlimApps, who released a Substrate extension for Cydia called TweakHub.
The idea: automatically determine what applications a Substrate extension is designed to modify, and use that to provide categorized lists based on the iOS applications you have installed.
This technique is exciting, as it does not rely on repositories and developers to manually tag packages (this never works out): most of this information is already picked up automatically by Cydia's "whole package index" :D.
(Oh, if it isn't yet clear why UnlimApps wanted this feature: they develop a number of app-specific extensions ;P.)
Clearing Caches Could Kill Cydia
A user reported a situation where they ran out of disk space, iOS cleared their caches, and then Cydia wouldn't run.