> the Cortex-A9 is the most impressive variant so far.

Yes, so far Cortex-A9 leads the bunch. Just for fun I compiled a small list* of DMIPS per MHz and core figures for various recent and future cores implementing ARM ISA:

ARM Cortex-A8: 2.0
Qualcomm Scorpion: 2.1
Marvell Sheeva PJ4: 2.4
ARM Cortex-A9: 2.5
Qualcomm Krait: 3.0...3.5 (estimated)
ARM Cortex-A15: 3.5 (estimated)

* Edit: updated list there

> If it wasn't a little buggy, I would already be using a Pandaboard.

There are also other Cortex-A9 boards, for instance the Snowball (available end of Q2/2011 starting at 225 USD):

http://www.igloocommunity.org
http://www.calao-systems.com/articles.php?lng=en&pg=6186
http://www.youtube.com/watch?v=ZUpgpjJl-5g

[ Edited by Andreas_Wolf 14.11.2012 - 00:49 ]