I have just recently (last week) finished updating two 2.2 drivers to 4.0. I feel that I could probably answer questions about it, or writing a driver from scratch if anyone would like to know.
New HTML Parser: The long-awaited libxml2 based HTML parser code is live. It needs further work but already handles most markup better than the original parser.
Keep up with the latest Advogato features by reading the Advogato status blog.
If you're a C programmer with some spare time, take a look at the mod_virgule project page and help us with one of the tasks on the ToDo list!