The removal of public key requirement needs a hard fork, which has been scheduledafter noon GMT Monday April 13th 2015
After the hard fork, supposedly only the 0.4 FIMK server series will follow the official blockchain and will be able to forge. Most active nodes are already updated, but occasionally a couple of 0.3 servers are visible in the network.
If you're using mofowallet from https://www.mofowallet.com/launch.html
, or using another 0.4.x server, no action is required.
0.4.2 with bugfixes related to browser access and ssl websockets should be released before the fork.