I recently upgraded one of my Xbox's and my PS3 from 1.8 to 1.9 and started getting freezes every couple of hours of playing, although the freeze I just got resolved itself after a couple minutes while I was typing this.

I've got another Xbox that's still on the 1.8 patch, and I played it for about 10 hours last weekend without a single freeze. So far, the 1.9 patch seems less stable.
Meow long can you play between freezing and what patch are you using?

I always found that 1.9 was less stable than 1.8 on the Xbox 360, but it seems people have had different experiences. Like you, I definitely noticed a big increase in the number of freezes after upgrading to 1.9 back when I played Skyrim on the Xbox console. I switched to the PC about 2 years ago out of frustration from the issue and don't get any of that type of behavior with 1.9 and the Unofficial Patches (for PC users) installed. The console versions are badly bugged too since they don't have access to bug fixing mods like the Unofficial Patches, which I'm sure is another major factor.