Jazz piano with some some stride and some walking bass. The "trick" with both of them–if there's a trick–is to play them softly at dynamics much lower than whatever's happening in the right hand. If you're interested in lessons or if you have a question about stride or walking bass lines contact me at firstname.lastname@example.org.
About the piano on which I'm playing: It's a Steingraeber Phoenix 205. Steingraeber is one of the great European piano manufacturers. The first 205 was built for Franz Liszt. The "Phoenix" part of my 205 is an set of innovations engineered by Richard Dain (in the UK at Hurstwood Farm Pianos). It's often thought piano manufacturing as an industry is staid and conservative industry–and perhaps it does appear that way– but nonetheless Richard Dain and Steingraeber have introduced many exciting innovations–including the Phoenix system.