My Tablo asked me to update yesterday. So, I did.
I had what I thought was a problem worthy of a bug report but as it is almost rolled-out at this point, the bug report is probably pointless.
Since I haven't used my Tablo much since summer re-run season started, it hasn't done a guide update it quite a while. After the update to 2.2.16, the guide data on Live TV was missing on most channels. They would play live just fine but no guide data.
I went into set-up and noticed there is an "update guide data" button, so I pushed it. All is fine now.
Might want to add a one-time task post-install to force a guide data update in the future.