The latest x8 firmware news and releases from the XDA forums are as follows:
GingerXperia V10 – based on MiniCM but with Xperia apps and nice styling
A lot of users have had success installing the official CyanogenMod release due to the [GUIDE] How to Install Cyanogenmod 7.1 from Stock 2.1 on XDA, you can check out the FreeXperia development thread here. The latest release is FXP042, main missing features are full camera support and FM radio.
If you’re not up to date, or starting out from scratch here’s some links to get your device rooted and a recovery installed:
If you’ve tested or use any of the firmware listed please give feedback to other users via the comments.