The existing templates haven't changed so if you previously switched to a different template, that choice remains intact. Two new selections were added and the default was switched to the selection named 'paper' if you want to see what the new default looks like. Sorry for the confusion.

The selection named 'experimental' is the same as 'classic' except with Comic Sans MS for the messages font as I recall. Personally, beyond the folksy feel it's more readable for my ageing eyes and monitor.