Recover large forum from Google 'Metafilter Penalty'?

Question

We have been one of those forums affected on Nov 16, 2012 (yes, 3 years ago!) with a very big drop overnight (from 800.000 unique visitors before that to 400.000 now).

Since that time we were not able to grow anymore in traffic, in fact we end every year with less traffic.

There was an interesting discussion here about this problem, which affected a lot of UGC sites.

And on last year this change was even confirmed by Matt Cutts due to the buzz generated by the Q&A site MetaFilter.

Things we have done on those 3 years without any noticeable effect

• Noindexed tag pages

• Noindexed member profiles

• Pruned old threads

• Added rel="next", rel="prev" for pagination on threads

• rel="nofollow" for external links

• Removed threads below certain word count.

Based on the 'ugc' context what else could i do to recover from this past Google update or at least improve the SEO of a forum?

Answer 1

i think that was mainly a quality update. And quality means in this case SERP CTR and user metrics. According to it should you move:

• establish something like voting for answers, like best answer flag, and for discussions, like important thread flag. let be indexed only answers/discussions with a certain minimum of flags.
• look at search traffic and bounce rate of discussions. let be indexed only discussions, which get a certain traffic amount and bounce rate.
• establish in each category something like hall of fame or sticky for good, long, evergreen discussions. let them be indexed.
• noindex all threads, which don't reach your own minimal margins of traffic, bounce rate and flags after two weeks after publishing.

On this way you will have in index only discussions with good traffic, low bounce rate and loved by users (flagged as best).

And don't forget to de-index your internal search and parametrized urls. Your main goals should be:

• less unimportant, SEO-irrelevant pages in index,
• more important, SEO-relevant pages in index

These two steps

• Pruned old threads

• Removed threads below certain word count. go into rioght direction.

Answer 2

...we were not able to grow anymore in traffic, in fact we end every year with less traffic.

UGC has a huge role in forums. If such content is meant to be quality content that is to be indexed in search engines, then consider having new information reviewed before it is posted. If not, people could post one-line messages like "ok" and "i agree" or even bad content which includes swear words and/or obscene content. Such text wouldn't count as valuable content to the majority of the users unless of course someone was searching for a forum with multiple short opinionated answers.

Also, check the keyword density of the content that's submitted. If it looks spammy, then remove it. You don't want content such as this:

"I have a black steel frying pan and grey steel frying pan. The black frying pan is made with steel and the grey frying pan is made with steel. The grey steel frying pan is made just for eggs and the black steel frying pan is made just for sauce.".

As you can see, I overused the words "steel frying pan".

Also, make sure the content submitted is relevant to the topic at hand. For example, if the forum is about gardening, you definitely don't want a post about pornography published.