First, there was a massive code clean up and removal. XMLRPC, SOAP, and HTTP Polling are no longer supported and have been removed. Also, versions of Twisted older than 2.5 are no longer supported. Similar, versions of Twisted Words older than 0.5 are not supported.
Second, speed increases have been made to the handling of xml and requests. There have been code improvements and protocol support fixes. There are protocol and unit tests too.
Also, Version 1.0 is close and should be out very soon.
Finally, in order to answer 'Which BOSH server do you need?'. Look for examples and demos of strophe and other software and technology using Punjab! These examples will be on here and the Punjab home page.