Looks like O'Reilly agrees with the results and even offers arrays as a third option when dealing with more than 10 conditionals. So O'Reilly suggests if/else for 1 to 2 conditionals, switch/case for 2 to 9 conditionals, and arrays for 10+ conditionals:

http://oreilly.com/server-administration/excerpts/even-faster-websites/writing-efficient-javascript.html

Guessing some of those optimization blogs screwed up on the if/else and switch/case.

So I guess we now have a new best practice for conditionals. Can someone please ensure this best practice is implemented for v4.0?

Lots of other good stuff on that page (some of which we already implement) that can help us tweak even further for v4.0.