I think that participating in the runoff, though I agree with the assesment that Tsvangirai most likely won outright in the first round.
Hopefully, with the rest of the world watching, and (hopefully) Thabo Mbeki sidelined in the process, the MDC can win the presidency.
That being said, there is a pretty good chance that Morgan Tsvangirai will be whacked by someone working for the ZANU-PF.