CityVille's Population Now Twice That Of South Africa

Based off a population list on Wikipedia. Zynga's follow-up to their casual mega hit FarmVille has broken barriers according to Mashable.
AppData, a site that specializes in Facebook (Facebook) app metrics, has CityVille at 99.9 million monthly active users, but since (by AppData's count) CityVille has been adding nearly 400,000 new monthly active users every day, the 100 million MAU milestone will surely be reached in the next update.
I confess I have never played CityVille or FarmVille. I avoided them like some sort of plague but now...now I am curious. What waits for me on the other side? Sword in hand I do declare it adventure time.
Feel free to comment if you can explain what would take 100 Million people's attention by storm.
"CityVille" Reaches 100 Million Monthly Active Users [Mashable]






We started CityVille recently due to a request from a family member, who needed "one more neighbour", and now it's our top productivity sink. If we're not waiting for energy points to perform actions we're busy rearranging buildings, flowers, begging everyone for supplies, visiting our neighbours, rearranging the town once again...
Avoid!
But as to why it's addictive? Probably the easy sandbox gameplay, never-ending goals, the fact that you need energy to do stuff and so can't just do everything in one go, probably.