The first-ever open Q&A session hosted at Facebook in Menlo Park on Thursday by Facebook CEO Mark Zuckerberg was not as interesting as expected, but let's see some highlights. The Facebook CEO spent about an hour answering questions submitted from around the world, including some from Facebook users who flew to the company's California headquarters for the event.

Possibly the most intersting answer was related to the strengths of Facebook's data centers and whether they could handle future traffic.

Zuckerberg responded that the real challenge was improving the infrastructure to allow for more rich media like video in people’s feeds, adding that most of Facebook would be video within the next five years.

Zuckerberg also said that the decision to force users to download Facebook's Messenger app for mobile was not easy but Facebook thought it "could provide a better, faster messaging product if it split it off from its own app."

He reiterated his determination to add high-quality, free phone calls to the list of services that Facebook provides — a plan that won’t endear him to the cellphone carriers that the company works with around the world. "Free calling is certainly something that we’re focused on," he said — as is delivering Internet service from satellites and highflying planes.

Zuckerberg also discussed one of Facebook’s failure to rollout of a new look for the Facebook news feed on desktop computers that featured much bigger photos and images. He said the company had made the changes in response to complaints that the design of the news feed felt outdated.

Zuckerberg said its goal was to make Facebook "cool" although he described himself as not a "cool" person, and that their model was to make Facebook useful rather than particularly exciting to use.

He also talked about the importance of diversifying the tech sector, saying that diverse teams perform better although less diversity in the tech sector was normal as girls don't self-select out of doing computer science education."

Another asked why he always seems wear the same t-shirts and hoodies. Zuckerberg said he wants to spend as much time as possible on things that matter, like how to build products, even if it means thinking less about what he wears.He cited other leaders with similar reasoning, including Apple co-founder Steve Jobs, who was famous for his signature black turtleneck and jeans.