We've been busy updating some rules and adding extras, lots of changes to a lot of rules. Mostly a maintenance release with some new scada rules.
The scada rule set now includes support for OMRON FINS. Additionally, multiple rules in the specific-threats and content-replace categories have been updated to provide more accurate detection.
More details available here: http://www.snort.org/vrt/advisories/vrt-rules-2009-03-17.html