Magnus: I found the taguchi tests to be nearly useless. I always used the PHP split test option. With mine you never need to upload files or mess with your old files. The entire test can be created on screen.
Donovon: I haven't used google optimiser but the fact that it uses JS alone is enough to turn me off. Javascript only tracks 90 something percent of your traffic. Mine does 100%. Also mine has features like one click to instantly implement the new best version. With Google you'd have to manually make the page that it says is best and upload it.
I'm going all out... it WILL become the new standard for multivariate testing.
Tynan