It has been six months since the last major release (1.7). During this period the Tiki team has grown from 68 contributors to 190!! Detailed stats here: TikiCommunity
For the last several months, Tiki has been eating it's own DogFood and using Tiki 1.8 on tikiwiki.org Three release candidates (over three months) later, the Tiki team is proud to release Polaris.
The main major new feature is a complete rewrite of all the queries to move to the ADOdb abstraction layer. This makes Tiki highly portable and useable with your favorite database. Tiki 1.8 boasts over 65 new features & enhancements. Congratulation to redflo for managing this release.
A unplanned 1.7.5 has been drawn up for the 1.7 TikiWiki release family. This is only a bugfix release and will not contain any new features.
TikiWiki 22.214.171.124 has been released! Thanks to all the developers for their hard work.
(126.96.36.199 fixes a blocking wiki edit bug in 1.7.1, sorry for the inconvenience)
Read on for summary of fixes and changes.
The main point in that release candidate is the fixed registration. It was blocking the rc2. If you use the 1.7rc2 you should upgrade to rc3. There is no db change, only some files fixed.