I don't know for sure because Camino lost some serious development time and Safari is still getting some features that Camino already has...
It may look like Camino had some downtime, but in reality, there was lots going on behind the scenes...
The move to the current Mozilla trunk is going to take a couple of weeks before it's stable, but it will be well worth it. The improvements in speed, rendering, etc. will be well worth the wait.
Also, although Safari is progressing quite fast, keep in mind that it's development answers to one man: Steve Jobs. If Steve doesn't like a particular feature - it's "steved" (86'ed).
With Camino, you have a voice (via the camino mailing list), and the developers listen to user input. Heck - if you have any Cocoa programming skills, you can d/l the source code and make your own improvements.
Whoever ends up on top, the bottom line is that OS X users have our own little "browser war" going on here, and it only means better browsers for the platform.
I'd rather use either of these beta browsers than IE for Windows anyday...