Founded by billionaire Tom Ricketts, TD Ameritrade is a publicly traded brokerage with over $1 trillion in client assets.  TD Ameritrade is known for discount commissions and superior support and technology innovation. 

Pro's:

The desktop platform thinkorswim is a low cost solution to many active traders in futures, stocks and stock options. TD runs it own media network and broadcasts market commentary and educational webinars.

Con's:
The TD Ameritrade thinkorswin is considered a more retail trading product and does not offer many of the algo execution alternatives of other platforms.