Is there a problem with new user signups?
I signed up this morning and pointed to hashcows, and while it's been acknowledging my hash rate all day, I haven't earned a single share. I've basically wasted an entire day mining so far as I was at work and couldn't point it at something else.
The FAQ is there for a reason, read it. It explains some of that and here is nearmiss' further explanation.
You won't see a change to your BTC balance until payouts happen, once a day at GMT 04:00:00. Normally you'd have an "Estimated Un-Exchanged" and "Estimated Exchagned" value that grows and adjusts throughout the day, those are currently disabled, and being worked on. If you don't have a balance *after* payout time, its something to be concerned about, and let support know.
I did read the FAQ. It says nothing about any of that except for the once a day payout.
The stats screen all day has shown my hashrate, but no accepted shares, no rejected shares and no balances. Excuse me for being a little concerned about that.