He only renewed a two year contract, this year being the second. As long as Webber is backing up Vettel and getting points and podiums then i think his seat woudl be safe at RBR. If he replicate of improve on last seasons performance then i dotn think that will be a problem. Until his run of piss poor results, stop gos at Spa, crashes etc he had a very good first half of the season. He needs to now be consistant the mid to latter part of this season.
Anyway, its all been said before and only time will tell. In my eyes the real test will be if RBR miss out on the Constructors title, will they be looking at Webber's performance as the reason. SO far this year, he made a qualy mistake in Bahrain and then got dicked by shared strategy in Australia and China. I dont think the team would be looking to lynch him as being the reason why they are where they are. Hell he led China and Aus but was dogged in Aus by the teams pit calls.