Though some people seem to continue to pit JSF against HTML 5, there is little practical reason this needs to be the case. In fact JSF 2.2 specifically and Java EE 7 generally has gone to great lengths to support the fellow HTML 5 body of standards.
It has always been fully possible to use native HTML in JSF pages. There is little reason you would have any practical difficulty in using most key HTML 5 features even with JSF 2.1/Java EE 6 including canvas, web workers, audio, video and local storage. The only clear place where JSF and HTML 5 can collide is while mixing and matching JSF features with newer input/data elements and attributes such as calendar, email, pattern, autofocus and placeholder. The JSF 2.2 expert group created a very novel and easy solution to this problem through pass-through elements and attributes. Using this feature you can start with an HTML 5 native element and add JSF features to it or start with a JSF element and add HTML 5 features to it seamlessly and effortlessly. By far the best write-up on this capability comes from Chicago based Java EE community advocate Josh Juneau. You should take time to read his very well written article published on OTN as well as the Java Magazine.
Washington DC based Java EE community advocate David Heffelfinger will tackle the topic of pushing HTML 5 usage to the max with JSF 2.2/Java EE 7 in his accepted JavaOne 2015 session titled Integrating JavaServer Faces and HTML5. If you can't come to JavaOne 2015 to see him in person we will share the session video with you on this humble blog when it becomes available.