Is there a way to determine how many games a person is in?
Numbers don't tell the whole story anyway. If someone is GMing a lot of games, it's very possible, but not certain, they are spreading themselves thin. It probably won't take much of a RL issue to mess it all up. How many someone is playing in is more problematic though. How active are the games? Do they involve short, basic posts, or require long, well thought out roleplaying posts? Does the player know the rules, whatever they are, well for all the games s/he's in, or have to keep looking things up? Is the person currently working/studying long hours, and how likely is that to change? I don't play much now that my health affects my ability to keep up, to learn new systems, and remember old ones, but what I used to do was add one game at a time, play it for at least a couple of weeks (especially if it was a new game, I find many of those have a big burst of posts at first, and then slows to a more sustainable rate), decide if I had time for another, rinse, repeat...