Okay, so this won't work in our phones, but... Every time a new higher capacity SD card has been announced in the past, very shortly after that a microSD card becomes available at half of the new capacity. Maybe we'll soon see 32 gig microSDHC available? My 16 gigger is over 90% full:
Full release re 64 gig SDXC is here:
http://www.toshiba.co.jp/about/press/2009_08/pr0401.htm