Just to add my two cent's worth about PMA: I'd advise against signing with this agency.
I was signed with Peter Miller for a year, and it wasn't a good experience. He was quite nice and enthusiastic in the beginning, but after I signed that wretched contract (the worst I've seen in the business, quite frankly) he pushed me off on an assistant and barely lifted a finger to sell my book. He was much too busy traveling around on speaking engagements, promoting the new edition of his own book on getting published.
There was great feedback on the book, but no takers from the first few publishers he pitched. There were several that he never bothered to follow up with. Communication with him (which was sporadic and infrequent) became increasingly more curt and, eventually, he was downright rude.
I've since heard from others that my experience with him is not unique. He is one of those agents that has a good reputation amongst writers who've never dealt with him, but people in the industry (editors, in particular) don't think very highly of him. His contract also demands 20% of domestic receipts and 25% of overseas earnings....much higher than any other agent.
I recently signed with someone else, and the difference is amazing. The agent I have now is motivated, loves the book, has a great track record, and most importantly, treats his clients with professionalism. He has sold many more books than PMA, plenty of them bestsellers, and yet his contract only asks for the standard 15% domestic/20% overseas split.
I'm glad that you have an agent who is interested in seeing your work, but don't stop sending out your stuff while you wait to hear back from PMA. Keep on looking, and if the opportunity presents itself to sign with anyone other than this agency....take it!