I have been hearing a lot about Seattle in the news lately, but I don't know much about the city.  Is Seattle the capital of Washington state?  
No I believe Olympia is Washington's capital. Seattle is however the largest city in the state of Washington. 
What is the population of Seattle?  I assume several million.
Estimated 713,700 residents. That also makes it the largest city in the Pacific Northwest region of North America.
That's amazing.  Is there anything significant either historically or practically about Seattle?
Seattle has been one of the fastest growing cities in the U.S. It must be great there, since everyone is flocking to it.
Do you know about any significant businesses there?  I know they have a professional football team that blew it in the Super Bowl against the Patriots.
Seattle is the home of Starbucks and Amazon. Two massive companies that started in the seaport city.
I had no idea about Starbucks.  I know Amazon has had some challenges out there with some of the politicians for some reason.  
Yeah I've heard from some Seattle natives that they really dislike how Amazon has taken over their city. Amazon ethics have been put to question.