Well, even if people didn't announce they had become sources, it wouldn't have taken long for others to notice. 
After a long time, theymos made an update to the list of merit sources. Some inactive sources were removed, some those who applied were accepted. I won't name names here, but it'll soon become clear who the new sources are.
An update regarding merit system was needed. I see this as a positive development for the forum. Good luck to all new merit sources. So 17 new MS if my calculations are correct. I see Theymos wanted to buy a bit of peace 
I feel sorry for the next person who will start a topic to become a MS, because he/she will be waiting a long, long time
. From what can be seen, 8 members have confirmed that they have become MS, and there are another 14 people on the public list who have applied, including myself. I haven't received any message yet, nor do I see anything changed on the sMerits page.
This would literally mean that there will be no new MS until the end of this decade.You never know with theymos.
He may well employ the rule of threes, meaning that he might do three things, and more than one of them might end up with the addition of more merit sources in a short period of time, so in that sense, he could even have two or three phases to his project of adding merit sources and making a few other revisions that go along with it that could follow within a month or two.
I am just guessing.. but still, we cannot presume theymos to just make a change, and then to sit on his hands for 5 years, especially if there might be levels and then the monitoring of repercussions in regards to the first actions... that might result in secondary or terciary actions to supplement and /or complement the previous actions.