Under Daily stats, Most Successful Raids Today,  I'm guessing should be "This Month" instead of "Today".  Is this correct or am I mistaken?

Aha, nice catch. I thought it was odd that a guild could do 500 days in a day when there aren't even enough guilds+npcs to raid that many times.

What happened was it was counting from the 1st of the month, instead of 00:00 of the same day.

I've fixed it now, afaik.