If you are like me, you have been checking your change for new quarters to add to your state quarter collection. According to a USA Today article, the state quarter program has been a big moneymaker for the Mint, to the tune of 4 billion dollars US when it reached the halfway point of the ten year program .When people collect the coins and take them out of circulation, the Federal Reserve has to buy more coins from the Mint. The Fed pays full value for the coins, which creates a profit for the Mint.
In my opinion, the process by which the states choose their quarters is too bureaucratic and ends up with designs that are compromised, not the most artistic or interesting one. Most states request submissions from its residents, then make a list of finalists which are presented to the public. A winner is chosen, which is submitted to the Mint, and then the state will revise the design based on the Mint's suggestions.
For example, look at the five finalists for the California quarter (sorry for the small images):





Here is a closer look at the third design by artist Garrett Burke, featuring conservationist John Muir "discovering" Yosemite Valley :

Here is the version the US Mint designed, based on Burke's design. The California condor above Muir's head was apparently added because of California Governor Arnold Schwarzenegger's request to try to incorporate the condor image.

Schwarzenegger ended up choosing this design, but he asked the Mint to simplify the design. This is the final result, which was minted as California's official state quarter:

If you look at the original design, I think it's clear that it is far superior to what the Mint and Gov. Schwarzenegger ended up selecting.
But some states do manage to get it right. Here is Oregon's state quarter, which was also released in 2005:

Here are some other designs that try to accomplish too much, throwing together images somehow related to the state:



In related news, the US Mint is launching its latest version of the nickel
(that's 5 cents to anyone unfamiliar with U.S. currency). This version will have a profile of Thomas Jefferson looking out from the coin. The nickel program, which began in 2003, commemorates the bicentennial of the Louisiana Purchase and the Lewis and Clark expedition.Also, Congress has sent a bill to President Bush authorizing a new dollar coin program, which is to feature four former U.S. presidents each year starting in 2007. The program is modeled after the US Mint's successful state quarter program, which will run through 2008.

An artist's depiction of possible designs for the new dollar coins.