Many people, including myself, have asked the question "what do I need to be successful?" Of course there are many answers to this question, but not to long ago, someone went and asked the fortune 500 CEO's what they thought was the most important skill. Over 80% of the CEO's said that public speaking and other communication skills is critical to being successful on a huge scale.
Yes, you can argue there are those shy-quite-nerds/geeks (I used to be one) that make it successful, but the percentage of those out there are very very few. Why? People use the smart people for their brains and then advertise their (not the smart ones) success. This was true for me in middle school and high school. I was a whizz at science, Algebra (I'm in trig now and grrrr, it makes no sense. Half the numbers you use AREN'T EVEN REAL! I hate it.), and economics. In middle school they used to give awards for people who increased their grades in a certain class over the year; well... a nice chunk of those who increased their grades in math and science because the teacher put with me. These people were absolute tards that should never be allowed to reproduce, but the teacher put them with me (hurting my grade) to give them the false hope that they could possibly be successful in life. (I know, that last bit was a little harsh). But who got the fame and credit for raising their grade? Them, not me.
This is how the real world works, and I have switched my ways to prepare for it. People will use the quite shy smart people. Because the nerds don't know who to get out that they are the ones that people want to hire, people will take credit for the nerds work. Maybe not saying "I did this work" when they didn't, but being part of the solution, even if you didn't help at all, but being able to say "I was a part of this", will really help your success in life.
The ability to be able to say "I was a part of this, hire me" or "I'm the best for the job" is a communication skill. Why is it some commercials stay with you or affect you differently than others? Because the people that made the commercial made the commercial to affect you in that way. That is a communication skill that quite people don't have. Look at the presidential races. Thomas Jefferson once wanted the people to elected the best person for the job, not just who was more popular. He soon found out this didn't work. John Adams, who knew people are dumb, advertised a ton. He knew that if he became more well known than his opponent, he'd win. Sure enough he did.
The ability to communicate will help you to succeed far more (on the average curve) than non-communication smarts. If you don't agree, look at what some of the most successful people said.