This is with latest Git master and Firefox 3.6.3.

I've noticed, when arrowing around, that the caret and cursor seem to get out of sync. Sometimes, for instance, I'll be arrowing through a document, will press tab, and am suddenly much higher up in the document. Here's how I can reliably reproduce:

1. Visit a site, say http://www.podiobooks.com.
2. Using the arrows, navigate down to the list of recently updated titles.
3. Once there, press tab.

Instead of tabbing through the list of recently updated titles, I instead find focus back on the login/register link much earlier in the document rendering.