From this source
http://wiki.blender.org/index.php/BlenderDev/SundayMeetingAgenda/November_25th_2007
The particle patch is ready for official merge, with the merging to be done by Jahka. It has been made as backward compatible as possible. brecht’s new hair render also will allow to render like 100 meg or more polys in a frame the same system we will make ready for grass, leaves
And then you’ll be able to render all that fur as well as tons of grass.
Good job Jahka, your particles will officially be in 2.50