Was the 'The' dropped from Lion's cover of the theme for the animated movie? By my recollection, it was...and it didn't seem to affect my enjoyment at all.
Maybe it''s because most series have subitles now, so the "the" is not as pretty when you say "The Transformers: Armada" or "The Transformers: Animated". (actually, that one kinda works)
I wouldn't really count that considering in that very same song they sang "When you're caught within the grip, of the evil UNICORN".
Maybe "The" was used more out of "necessity" in the G1 era. Due to the fact there were tons of transforming robot toys in stores already or coming soon (GoBots, Convertors, and other off-brand figures), maybe the use of "The" was used to add that little bit of punch to the name, to signify that "THE" Transformers were "THE" real deal, "THE" transforming toys to have, "THE" ones that defined what transforming toys should be. [I'd imagine Hasbro's marketing department might have decided "The" should be used.] With the later TF lines, "The" definitely sounds odd along with the subtitles. On a more serious note of why "The" might have been and should have been dropped: After G2 and Beast Wars, maybe after RID, Transformers were really the only toys of their kind on the market. Sure, there were/are other transforming toys, but those were/are part of other toy lines which had/have their own separate identities (Power Rangers comes to mind). There weren't many products or individual toy lines that were exceedingly similar to Transformers like the GoBots were, for example. To parallel my reasoning for having "The," Transformers had their own identity, so by the time we got into later lines of TF figures, there was no need to use "The" to differentiate them as "THE" real thing compared to what few similar toys there were on the market.
That word can make difference. Imagine title for next Transformers movie. It would be Revenge of Fallen. Entire fanchise would sound like it poorly translated without word. Notice I didn't use the word for my whole idiotic rant?