The arguments many Americans are making against using dollar coins are the same ones we Canadians were making in the lead up to the introduction of our $1 coin, the "Loonie". Some of the arguments are absolutely silly: ' the weight of the coins will make holes in people's pockets and create extra expense for clothing manufacturers!' I guess that since most clothing is made in China now, there won't be much of a US clothing industry to appease.
In a nutshell, it boils down to people's aversion to change. (*triple points for pun*)
We have grown to love our $1 and $2 coins, the Loonie and the Toonie, and as a metal detectorist, I have to say, they can really add up fast. My short beach hunt yesterday paid off nicely (see a Toonie and loonies on the right):
What Canada did to introduce them was start prepping the public that the $1 bill was being eliminated with a pretty long lead time. Then the government introduced the coin and started pulling the bills out of circulation. Removing the bills from circulation is key. Within no time, people here were comfortable with the coins. So much so, that we gave them cute nicknames. When people start giving their money nicknames, you know they are hooked.
What you Americans need is a nicely designed coin, not something weird looking like the Sacagawea or Susan B Anthony - those are pretty hideous IMO. Considering your history of designing classically beautiful coins like the Mercury dime, and seeing as our national symbols are different (we like waterfowl, beavers, and bears, you Americans like freedom and liberty and blowing stuff up), perhaps something like a modern reissue of the Morgan or Peace Dollar would please most Americans...
You could call it the Freedom Dollar, the "freebee" !
Anyway, as an MDer, I love our Loonies and Toonies. I have already paid for my Whites M6 more than once, just with clad, and I only started detecting in August!