Maria over at Hypergrid Business has a write up on the latest Alchemy Viewer Beta 4.0.0. See: Alchemy viewer updates browser, chat bar.
The title tells you the big change in this version. Cinder Roxley, Alchemy developer, says they have surpassed the Lab in the implementation of the CEF browsers engine. Cinder is using the latest and greatest, I guess.
Word is this version catches Alchemy up to Linden Viewer 4.0.0.
Download Alchemy Viewer here.