Three Ounces
TSA seems to have lightened its restrictions on bringing liquids and gels on board. However, they must be under 3 ounces, which is above the 2 ounce size that mini shaving cream bottles come in. TSA will still allow the 4 ounces of saline it has allowed since August, which means bottles like this are still okay.
This is a glimmer of hope for the short-hop traveler. I pride myself in adapting well to TSA - no belt on travel days, slip-on shoes, etc - but showing up sans toothpaste and shaving cream has had obvious shortcomings. Sorry, I refuse to check luggage for an overnight flight.
Post-Script:
Pic added, as captured from this TSA document.