I’m reading a few books on online gaming, starting with Edward Castronova’s Synthetic Worlds. It’s mostly about MMORPGs, or MMOs as we’ve thankfully started to call them.

I’m about halfway through the book, which was published in 2006, and it’s startling how much has changed in a few years. As the book was written, World of Warcraft was just starting to take off — and the current crop of lightweight social games wasn’t even on the horizon.

Castronova spends some time talking about the number of folks spending their time in online worlds, and I wanted to know how those numbers looked now. So I headed over to MMOdata.net, which does a fine job of collecting those stats. (It’s worth spending a little time with their MMO and Accuracy list, a nice bit of data collection transparency.)

All the following charts are from MMOdata as of August 3, 2010: the charts are regularly updated.

The first chart is total subscriptions for all MMOs tracked — a pretty steady curve up, at least until the last 6 months or so.

The next tracks subscriber growth for the top MMOs (those with 1+ million subscribers):

Finally (and I find this the most interesting chart of all), the number of peak concurrent users for the largest shards. Most games control the number of peak users by adding more shards, and so aren’t shown — instead we see the two main worlds with no sharding. In other words, everyone logging on is in the same world at the same time.

Eve Online is an interesting example of slow, steady growth as a relatively minor game world.