I have this same problem, but it happens on a regular text input, and only on the HTC Desire / Incredible running Android 2.1 / 2.2 right now. Other devices it appears to be working.
I'm using the latest build from the repository, 1.0.3.
The strange thing for me is, if I remove the cardswitch flow, and interrupt the the form submit with a return false; on the "beforesubmit" event, the keyboard will hide and the text field will blur.
I'm running a few tests right now, but I wonder if this has to do with the card switch triggering before the text field blurs (even though I call .blur() on the text field beforesubmit). This could be working in conjunction with Android taking over the text field drawling. Did you figure out how to give control back to the DOM?