The suckiest State Quarter by far is Wyoming. "Let's just slap a piece of clip art on it, nobody will notice!" Alabama's isn't that great, either. Helen Keller? The best thing they could find to represent the state of Alabama is Helen Keller? It's hard to say which one is the best, there are so many good ones.
Next year, the US Mint will be issuing 6 quarters representing the US territories: the District of Columbia, Puerto Rico, Guam, American Samoa, the US Virgin Islands and the Northern Mariana Islands.
The Mint will also be redesigning the penny next year, with 4 new coins representing various stages in Lincoln's life: His birth, childhood, his life as a lawyer and finally President. The penny from 2010 and beyond will have a new reverse design representing Lincoln's preservation of the United States.
Unfortunately, I've gotten started on a new collection, Mint Proofs of the Presidential Dollars. These are coming out 4 every year, starting with Washington at the beginning of 2007 and running at least through Ford in 2016. Interestingly, there will be two of Grover Cleveland, as he was both the 22nd and 24th President. Apparently they are stopping at Ford, which means there will be only 2 Presidential Dollars in 2016; I have no idea why they're not doing Carter and Reagan (or for that matter, Bush, Clinton, Bush Jr and Obama/McCain, that would make another year's worth).
I think I shall skip the First Spouse 1/2oz gold coins; they're over $600 each. 4 are released each year at the same time as the newest Presidential Dollar, which means I'd have to spend $4800 just to catch up; assuming the price of gold remains the same, the full set of 38 coins will cost at least $23,000!