OK here's an update. My hubby talked me out of rushing to the vet because Malone is doing quite a lot better. He slept all afternoon (that's mostly normal) and when he's awake he's pretty active. In fact, I was in the dining room, and he wandered into the kitchen. 30 seconds later, I followed him, and he was SITTING on the counter (how did he get up there?) eating the cat food. Yikes! There wasn't too much in there to start with, so he didn't get very much, thankfully. So, we are just continuing to watch him carefully, hope he gets all his energy back by tomorrow, and waiting to see if he will have any more diaherria. Thanks for all of your support!!!