Well it looks like it will take a while before we see a new Peak Concurrent User record in the "Peak Concurrent Users on the Largest Single Cluster servers" from either EVE Online or Second Life.
However, there are good reasons for this, and it is not because the mmo's are getting less popular ...
For EVE Online it is because of the heavy fight from CCP against illegal RMT and the accompanied macroers and account hackers, also called "The Unholy Rage".
The impact during this summer was very big in certain areas of the server, and in one instance during the unholy rage, the overall PCU dropped around 5k.
You can read this in the CCP dev blog here :
CCP Devblog Unholy Rage
For Second Life it is because of the new Bot policy. Which restricts the use of traffic and camping bots. The PCU dropped around 8k initially and will probably drop even more as landbots will be slowly replaced by web tools.
You can read about it here :
Second Life blog about the economy
And here :
Second Life blog about bots
Still both operations will result in an overall better and healthier gaming experience for both games. In EVE Online you can already see the PCU is slowly getting back to the level where it was in June, I will not be surprised if we see a new record soon. Also Second Life will certainly go up again, and the PCU will consist of a lot more actual players and less bots.