Let me know if anything's broken.

Checked out rev 695 and  couldn't get it working right, (probably udev problems) so I just reflashed entirely
with the rootfs you linked.

I can get into it, but it fails to bring up usbnet properly.  A gumstix still running 2.6.11 works properly.

From the linux host, I can see gumstix packets coming up usb0, and I send replies.  I get
NETDEV WATCHDOG: usb0: transmit timed out
in dmesg on the host.

Has the on-the-wire protocol changed, and do I need to upgrade my host to 2.6.14 as well?
it's currently running

dmesg on gumstix:
Freeing init memory: 60K
NET: Registered protocol family 1
pxa2xx_udc: version 4-May-2005
usb0: Ethernet Gadget, version: May Day 2005
usb0: using pxa2xx_udc, OUT ep2out-bulk IN ep1in-bulk STATUS ep6in-bulk
usb0: MAC 0e:00:f4:41:51:e1
usb0: HOST MAC 0e:00:f4:41:51:e2
usb0: RNDIS ready
usb0: full speed config #1: 100 mA, Ethernet Gadget, using CDC Ethernet Subset

dmesg on the host:
usb 1-1: new full speed USB device using uhci_hcd and address 6
usb 1-1: configuration #1 chosen from 2 choices
usb0: register usbnet at usb-0000:00:04.2-1, Linux Device, 36:57:d2:58:17:95
device usb0 entered promiscuous mode
gumstix: port 2(usb0) entering learning state
usb0: no IPv6 routers present
gumstix: topology change detected, propagating
gumstix: port 2(usb0) entering forwarding state
NETDEV WATCHDOG: usb0: transmit timed out
NETDEV WATCHDOG: usb0: transmit timed out

Again, unplugging the 2.6.14 gumstix and plugging in a 2.6.11 just works.