That was Grigory Sokolov in a concert performance of the Sonata Hob.XVI:23 in F major. 2002 was a good year to be attending Sokolov concerts if you were a Haydn fan. He seems to have had three different Haydn sonatas in his touring program that year. Here is the Sonata Hob.XVI:34 in E minor:
And the Sonata Hob.XVI:37 in D major:
Here is another recording of the same three sonatas in a different concert from March 2002:
As you can hear, these performances are different in interesting ways. The tempi are subtly different, as are the articulations and the dynamic scheme. A lot of touring virtuosos deliver exactly the same performance in every concert. This is the safer course, but it is aesthetically less satisfactory because there is a significant element of mechanical reproduction--that's the problem with audio recordings, too. But Sokolov, dedicated to the live performance, and one that is, on this evidence, truly live in that each performance is a bringing to life of a musical entity, not just finger-spinning, does not take the safe course of just delivering a technically sound performance, but instead gives us a transcendent and luminescent one.
As Donald Francis Tovey claimed, Haydn is really one of the most important composers in music history, but rarely honored as such.