The CyanogenMod 10 Preview has been ported to the Galaxy Tab 2 7.0 and the Galaxy Tab 2 10.1. These ROMs are a preview of what is to come in CyanogenMod 10 and are currently the only way to get Android 4.1 Jelly Bean on those tablets.
Before you install these ROMs understand that there are bugs and make a backup so you can go back if anything goes wrong.
There are also CM10 builds available for the Galaxy Tab 10.1 and the Galaxy Tab 8.9.
Samsung has not told us which devices will be receiving Android 4.1 Jelly Bean, but I will make some educated guesses based off of past trends. Samsung usually gives one core Android update. The updates do tend to take quite a long time though. First let me tell you which devices almost definitely will not receive the update. The original Galaxy Tab, Galaxy Tab 10.1v, Galaxy Tab 10.1, Galaxy Tab 8.9, Galaxy Tab 7.7, Galaxy Tab 7.0 Plus, and the Galaxy Note will not get the update. Most of those devices will end up on Android 4.0 Ice Cream Sandwich though.
The Galaxy Tab 2 7.0 has been praised for being an affordable tablet with mediocre specs. It was a great option for people wanting a moderately powerful tablet, but not wanting to dish out $400+ for a more powerful tablet. The Google branded Nexus 7 has been rumored for months, but now it is days from an official announcement at Google I/O. After it comes out, the Galaxy Tab 2 7.0 will not be a smart buy for most customers.
If you buy a Galaxy Tab 2 7.0 or Galaxy Tab 2 10.1, then Dropbox will give you 50 GB of storage for a year. After the first year you will be downgraded to 5 GB for another year. Then you will have the standard 2 GB. There are plenty of ways to get more free storage though. I have 10.2 GB free from referrals and automatically importing photos.
Overclocked kernels will increase the clockspeed on the tablet above what it is set to by default. For the Galaxy Tab 2 7.0 that is two cores at 1 GHz each. The overclocked kernel can boost them up to over 1.3 GHz. This is still in development and might cause crashes, so make sure do make a backup in ClockworkMod before attempting to flash this kernel.