On p2pool.org, it shows it has been 83 days since the last block, so are they not running jtoomin's fork?
Correct. The most recent block found on jtoomimnet was found on September 18th. Jtoomimnet currently has around 2.6 PH/s and an expected time per block of around 22 days. Mainnet has around 0.7 PH/s and an expected time per block of around 90 days.