I got one notice via email from Maryland saying that my application had passed through general screening and was being submitted to the individual department for review, and a decision would be coming my way "shortly". That was about 10 days ago, so their "shortly" might mean two weeks, a month, who knows.
And that's frustrating, awvish. I think that the way schools get around that is so they don't get inundated with emails and calls from people who are equi-anxious as we are (if not more). If they say "you will know by X date", and its a few days after that, people will just call and bug them, so I think they are trying to prevent that.
When they say "you'll know in a few weeks", that's not a definite time frame, so it allows for less phone calls and traffic in and out of their office. I'm only assuming this because we do that where I work. If someone submits paperwork for a grant or whatever, we have to give a vague "you'll know by" or "within the next few weeks" as a response, since a specific date would cause insane amounts of questions and phone calls to come our way if it's a day later. That might not be the reason, but I'm willing to bet it is.
It's still really crappy and frustrating.