Up until recently it's been our goal to stay no more than a full version behind the latest browser versions. Clearly that's not the case right now, and the reason is because our team has been very busy with something brand new that we should be able to talk about in the not too distant future. We understand that for the time being this is making BrowserLab less relevant and we apologize for that. Once we are done with that we plan to update our browsers and work on some other issues that have been on our backlog for a while.
Hope this helps,