I thought clapping on board was standard practice as the first time I flew back in 1988 was with El Al from London to Tel Aviv and the Israelis on board clapped when we came over the coastline and again on touchdown.
More recently, flying into Anchorage in 1999, we had a bumpy last few miles to touchdown followed by a firm landing which elicited a good round of applause and the following comment from one of the FAs; "Please take extra care when opening the overhead lockers as there is a greater than normal chance that some items may have become loose. Don't forget, shift happens."
And finally, just before Christmas I flew over to Germany with Mrs. Style and the stylettes on a very windy evening. It was blowing right down the runway at Stansted so we went up like a rocket but the final approach was quite lively to say the least and the mostly German passengers erupted in applause as soon as we were down. Alas, it didn't stop the elder stylette from being sick. Seat 2E on Air Berlin's 737-400 D-ABAH is the one to avoid...