Andrew Gregory has sent some information on a major conference in Oxford, April 7-10, 2008:
The Oxford Conference on the Synoptic Problem
This conference is designed to mark the centenary of the landmark conversations that occurred in Oxford and led to Oxford Studies in the Synoptic Problem (ed. William Sanday; Oxford: Clarendon, 1911). The purpose of the 2008 Conference is both to give a comprehensive assessment of the state of research into the synoptic problem over the last hundred years and to indicate potential ways in which discussion may be advanced. It will also highlight and critically examine key methodological issues that shape the way in which the discussion is conducted.
For a list of participants and booking form try here (not working yet) or here.
There is one paper on textual criticism and the synoptic problem (do leave any suggestions in the comments!).