Well they offer college algebra at my high school which is the same as MTH 135 at our state university, which is like a second or third tier algebra course at the college.
From personal experience, it wasn't much worse than algebra II. It's just mostly graphs, and once you get the hang of it it isn't too bad. I'm making a better grade in it than I was in algebra II, but that might just be because of a change in work ethic.
The main difference for me is the fact that homework is optional and worth no credit. You only get points for quizzes and tests, and the final is worth 30% of your total grade. I'm not sure if that's how it is at all universities or how they do it, but that's my personal experience with it. So it takes a decent degree of discipline over Alg II and your typical high school courses, or your grade will be shot with no extra credit or means of raising it.
Also, I'm taking trig at the same time and several topics overlap. Transformations of graphs, logarithms, quadratic, square root, circular, and exponential functions, interval notation, factoring, sequences and binomial expansion, maybe a couple more topics even.
You've probably had a decent bit of exposure to most of the topics covered in college algebra. It's just more extensive and covers a few extra types of graphs (rational, polynomial, logarithmic, linear programming).
I'm taking the final for it tommorow, so I'll tell you how that goes