Nothing came out in May except for LA Noire (which is really a very niche game) and Brink (which sucked). Of course sales would be down for the month. There were no big releases to drive sales.
^ word. It's hard to beli- well not really. People are stupid and like to panic.
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"The Daemon lied with every breath. It could not help itself but to deceive and dismay, to riddle and ruin. The more we conversed, the closer I drew to one singularly ineluctable fact: I would gain no wisdom here."
Great game, but not exactly a "big release" - there was next to no marketing for it, and it was a sequel to another game that was great but didn't really sell.
Not to mention that PC games tend to sell less than console games, unless it's WoW or Sims.