"Penumbra Overture EP. 2", well first of all it ended up being called Black plague.
after that came requiem which I think was a puzzle focused third penumbra game, made by a third party.
Then they made Amnesia TDD which many consider scariest game ever, even today 6 years later.
Then FG started work on the recently released SOMA, but while they were working on that they had TheChineseRoom make a sequel called Amnesia a Machine for pigs. This sequel failed to meet the expectations of a lot of players.
finally september 2015 SOMA released, and it was very well received, especially for it's story, though there seems to be a "general" consensus among reviewers that it was not quite as scary as TDD.
In terms of the community:
People started doing lets plays of amnesia, and amnesia mods, and this seemed to make amnesia modding go completely boom boom boom at some point in 2010-2011 I think.
White night was a really popular mod.
pigs never had the same following.
There was this guy named skashi once, who liked ripping stuff from games and putting it in his weird mods. This got him really unpopular with Moderators and his mods were eventually removed from the forum. Anyways even before he got removed there appeared to be this general kind of hatred towards Skashi and the content delivered by him, it was kinda hilarious.
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As well spambots seem to have essentially become part of the family here.
well thats some of the stuff that happened, lots more but I could keep writin forevar!