OpenLayers v2.8 has received its Final Release and is now the official stable release. New features introduced in v2.8 include:

• Support for multi-layer vector feature selection
• Support for drawing text in vector layers
• Support for 5 new layer types: OSM, ArcXML, pre-cached ka-Map, MapGuide "served tiles", XYZ layers.
  
• Support for the WFS protocol
• New controls: GetFeature, GetFeatureInfo, Split

The full set of release notes are here, and the release announcement can be found here.