I think it's just how many folks are on at a given time. Load related. At 2:00am U.S. Pacific Time...the new FlyerTalk has been blazing the last 2 nights. And this morning (a weekend mind you, when most folks are out and about away from internet) it's pretty fast too, but as more people log on it slows down. IMHO.

Weekdays and weekday evenings...aaaagggh.

You can almost watch the performance relationship looking at the number of folks logged on via the counter at the bottom of the main page.