The patch notes state this:
Players can now report RMT messages via a menu in the log window.

Any reports sent using this function will be processed automatically. When it is confirmed the reported player is sending RMT messages, their ability to speak with other players will be restricted.
Does this mean that all forms of communication are restricted, including /say? I ask this because while I noticed that pretty much the RMT bots sending /tells have pretty much been wiped out (I haven't received a single tell since patch thus far), the RMT bots spamming /say are still hanging about.

Honestly it wouldn't make sense to restrict /tell and not /say, and not all other variations of chat for that matter, as the bots clearly use and no doubt WILL use all channels available to them.