2.3.1-4 is pretty stable. Only problem we know of is that Asterisk 1.4.23 seems to be broken for *8 type call-pickup. Digium have fixed the bug in the svn trunk and released 1.4.24 but ATrpms haven't caught up yet.
2.3.1-6 is in test but won't be available to download until we've given it a shakedown. It's a big release with a lot of AGI optimization in it.
Best
S