Yes, I have used several usb sticks to boot on my AOA150 currently with Ubuntu
11.10. Strangely the software 'Startup Disk Creator' is fussy about which .iso
it will accept, it does ubuntu isos but not all others, so if you have trouble
try Unetbootin from the Software Centre. Until you get it working I suggest you
remove the other USB devices.
Occasion usb sticks can be difficult so I sometimes set up and format partitions
first using GParted and mark them bootable.

When using SD cards to boot,I find it easier the put them in an usb adapter.
Suggest removing the redundant devices fron the bios menu and leave usb drive at
the top, otherwise us F12 immediately after the bios to get the bootup menu.
You'll find Puppy great, woof!