What file systems can be used on the SD card?

[Guest DoctorWkt]

I've just ordered a locked streak + a rebel simcard for use in Australia & currently waiting for delivery. I had an old windows mobile device and I'm sick of fighting VFAT, so my question is: what filesystem formats can be used on the removable SD card on the streak? I'd be very happy to use ext3fs, or even ntfs if I had to, but anything but VFAT please!