There are a couple things I haven't figured out yet, the main one being the API for starting up a BeautifulSoup object with a given tree-builder. I'd like it to be as simple as passing a string like 'lxml' into the constructor, but I haven't thought through the details yet.
Sun Jan 30 2011 22:47 Beautiful Soup 4 Status Report:
The port is going pretty well. I've got almost all of the old test suite modernized and ported to the new framework, meaning that BS4 now works about as well as BS3.
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