Flowplayer HTML5 is not a new version of the old Flowplayer. It’s a completely different product. There have been other threads on here about it. Chances are you want to stick with the Flash-based version.
Actually there is some streaming in HTML5, but its browser-dependant and not really well supported, so you probably can’t use HTML5 video tags for streaming just yet.
HTTP Live Steaming is a new thing, (I think). To stream RTMP you’ll need a Flash based player.