Interesting, isn't it. BA 268, 20th February 2005, has a surge on take-off from LAX. Far from declaring a Mayday, a decision was taken to fly back to London on the remaining 3-engines. That decision was robustly defended here on PPRuNe by people professing to be B747 pilots, which I'm sure they were, at least 95% were, mostly on the grounds that A B747-400 is a different animal, and that flying it LAX-LHR on 3 engines is no less safe than with 4. (Provided you get your revised fuel calculations right, of course.) A few dinosaurs disagreed, repeating the mantra, "Land as soon as safe to do so" if an engine gives up the ghost. I don't remember anyone criticising the lack of a Mayday call.
My point is, what's different about this latest incident? I'm guessing that something was, but what?