With Panda still ongoing, it's difficult to work out if a site is being hit by Panda or has tripped another type of penalty.
One site in particular I work with has recently seen a large drop in organic traffic from Google. Strangely, however, it still ranks highly for some very competitive phrases while other pages are nowhere to be seen in the top 100.
Recently AJAX pagination was added along with lots more original copy on categories. I'm wondering could it have been penalised for being too optimised? I'm assuming it may not be Panda as it isn't a site wide drop in rankings. Or perhaps I'm wrong?
Any insight would be appreciated.