The days of web development specifically for a computer are over. Many people use their mobile devices to browse on the web and expect to have a pleasant experience. For developers, creating a website that works on many different screen sizes can be very frustrating and testing can be a nightmare. Bootstrap is an incredible tool that makes responsiveness easy.
Having used bootstrap myself, I can say that it saves a lot of time and a lot of headaches. I never have to worry about responsiveness and it helps tremendously with site layout. Stylization is not easy, but bootstrap provides a core of elements that can be used together and placed on a grid.
Bootstrap templates can also be used for even quicker customization. Many sites are adopting bootstrap and it is open source so the community will keep developing for it. Every information professional should be concerned about responsiveness and layout so I encourage you all to check it out at: http://getbootstrap.com/