Hi
If you are a premium member login here and open a ticket:
http://support.wordfence.com/support/tickets
I have opened 3 today - the sites I have not upgraded are also having issues. Mark is normally right on top of this stuff - the silence today is odd. In my opinion. I would guess some serious troubleshooting is afoot!
I would recommend using the same subject line "WordFence API error!!!" so this all is viewed as the same issue! And include the text johnflufin used - if that is the error you are seeing!
Just updated to WP 3.8.1 and installed WF 4.0.1. I'm getting this error:
Scan terminated with error: WordFence API error: Your blog is using an unsupported WordPress version. The version we received was: 3.8.1
Found some other posts about this error. Replies from WF rep indicates this is an issue with WF server playing catch-up.
Any idea when it will be caught up?