A 30s gap over an entire race isn't that big of a deal, Hamilton won the 2008 British GP by over a minute but that was changeable conditions. Watch the first lap of any race and see the gap Vettel builds in a single gap, it has hovered around 2 seconds for many races...
I think it was Singapore where a safety car blew out Vettel's advantage and the pack caught up. Obviously tyre wear was very low in that period, so the team told him to put his foot down, at which point he again managed to increase the gap by about 2s per lap to the point where he had gained back an entire pit stop. Even with a favourable track, I'm sure those in the paddock can't help thinking of the similarities with the 1994 season.
http://en.wikipedia.org/wiki/1994_Formula_One_cheating_contr...
Yeah, huge gaps aren't evidence of cheating. There was once race in 2003 or 4 when Schumi lapped the entire field up to 3rd place. He technically came in 1st and 4th place. :)
