Megatron's resurrection on the ocean bottom and his subsequent flight into space mimics a similar scene from the movie Transformers: Revenge of the Fallen (2009).
The backstory of the great Transformer relic, the AllSpark, is very similar to the one detailed in Transformers (2007). Not surprising, as producers Roberto Orci and Alex Kurtzman have also worked as the script-writers for that movie.
The poster and DVD case of the movie depicts Optimus Prime facing off against Predaking. In the movie itself, the two never meet.
Originally, the movie would have featured Airachnid teaming up with Unicron and Megatron. Plans were scrapped, thus Airachnid is absent from the film and her final fate was left up in the air.