The second week of the Shadowlands pre-patch event brought a continuation of the Icecrown scourge quest line, some additional dailies, the Scourge plague, and the reduction of rare spawn timers from 20 minutes to 10 minutes.
I liked the scourge quest line. It had some infiltration bits revealing the bad guy, some aerial bombardment from a gryphon, and a final fight against one of the new Shadowland enemies (I assume). Then back to Stormwind for turn-in and a Feat of Strength.
The Scourge plague is pretty fun. People become zombies and then attack other players. If you die to a zombie, you become one and can continue spreading the plague. There are lots of outbreaks in Stormwind and Goldshire. I went to Westfall to spread the plague there. I'm sure many people are unhappy about "interruptions" in their standard game-play, but I'm a fan of shaking things up for a week or so.
Regarding the new rare spawn timer, I think cutting the timer from 20 minutes to 10 minutes was a mistake. The servers have become noticeably less stable, especially around when Bronjahm (who can drop a 34-slot bag) spawns. 10 minutes has made it much easier to farm rares, and I think more people are staying online to do so, rather than going and doing something else when the next spawn is in 20 minutes.
I've collected the sets on my Paladin and Rogue, and have almost finished my Mage and Shaman. I think that will be enough for me.