It's a lot leaner, so if you are used to fatty red meat, you might take awhile getting used to it.
Otherwise, it's sweet. Literally.
Here is a great source of grassfed meat. It's called North Star Bison and can be found at northstarbison.com
the bison are basically free ranged over zillions of wild acres in Wisconsin, and are not fussed with. The prices are less than most sources of bison, it's cleaner than other sources of bison, and the shipping (at least it used to be) is ridiculously affordable. I used to get 50 lbs of bison shipped over night for a mere $20 shipping charge.
Since taking up hunting and knowing lots of grass feeding ranchers around here, I do not need to order from them, but lots of people in LA do just that. While I still lived there, most of the people I knew considered that the best place to get grassfed meat.
That was like ten years ago, so I'm sure there are plenty of options now.
That website does offer other meats now, if you order stuff from them, let me know how your experience goes.
Another great resource is eatwild...
http://www.eatwild.com/index.html