Here they are, Ubuntu Natty packages of the OpenCV 2.2 branch, revision 5206. This is, at least at the moment of writing, the most recent, stable and bugless version of OpenCV available. You can see this as the probably/maybe/hopefully upcoming 2.2.1 release.
Differences to original Ubuntu packages:
OpenCV 2.2 branch revision 5206
libcv2.1, libhighgui2.1 and libcvaux2.1 are replaced by libopencv2.2
libcv-dev libhighgui-dev and libcvaux-dec are replaced by libopencv-dev
CMake file is included in dev package
training binaries are in opencv package
TBB is enabled
SSE3 is enabled
$ sudo add-apt-repository ppa:gijzelaar/opencv2
$ apt-get update
$ apt-get install libopencv-dev
For more information have a look at the PPA. Let me know if there are some problems in the comments, but please don't e-mail me about OpenCV related questions. Use the OpenCV user group for this.