There are lots of call-outs to old films, the star "George Valentin, played by Jean Dujardin, is a combination of John Gilbert, Rudolf Valentino and Douglas Fairbanks. You get a Keystone Kops moment, a bit of swash-buckling, an actor disappearing into quicksand, a call-out to the first sound scenes in "Singing in the Rain" with the fixed microphones, and a very clever dog, like the terrier in the 'Thin Man' films. There was also a cheerful dig at the historical inaccuracy of the old films, where after a sword fight with costumes reminiscent of the Three Musketeers, Napoleon suddenly stands up :-)
They have a lot of fun with the idea of talking in pictures - the opening scene shows the hero being filmed in a scene where he is fiendishly tortured, and the intertitle (a word I never knew before!) comes up with "I'll never talk". But he does, right at the end, and with just the right words.