Is the hero of a sci-fi movie really very different from that of a Greek myth?
From a narrative and aesthetic point of view, there are obviously many similarities, which have also been much studied by academics, I'm sure. But few, I think, seriously consider modern sci-fi and fantasy as source material for religion and spirituality, whereas old myths were inseparably intertwined with the religion of their time. (There are some notable exceptions, of course, such as the followers of the Jedi faith.)
But if we take the premise that deities and their ilk are concepts invented by us, symbolic of the forces that drive the universe (including our own minds), then the origin or nature of these concepts shouldn't really make much difference.
I have written earlier about my 'animistic' (for lack of a better term) ideas about how each entity, whether physical or merely conceptual, interacts with each other, thus helping to shape the world. It is this interaction, the effect an entity has on an individual or society that defines a 'god'. And in the modern age, don't the heroes of contemporary fictional works play a much larger role in the daily lives of many of us than any ancient mythological character?
I quite like the term 'apotheosis', and it does hold some relevance to this topic. It is defined as 'the elevation of someone to divine status'. The protagonists of fiction are rarely gods these days, but I don't see any real reason why they could not be treated as such. Deification of mortal heroes (both legendary and historical) was of course by no means unheard of in ancient cultures. The Greek had shrines ('heroon') specifically for the worship of heroes, and the hero cult was of great importance in their society. A 'hero' ('heros'), by definition, was something more than a mere mortal, a demigod even. As Wikipedia puts it, a 'hero was more than human but less than a god', although the distinction is hazy at best.
The new aeon is an age of choice, more than anything else, an age where we are no longer bound by any one tradition that raised us. One myth is as good as another, it is what we get out of it matters. The term 'hero' has, of course, suffered from some inflation since antiquity, which is why few associate religious importance with it these days, but I see no reason why the old Greek ideas concerning heroes could not be applied to modern characters.
This change in the way we understand the word 'hero' can of course be seen as boon. Just think of all these cool new demigods popping into existence all the time! And there is a lot of choice, to say the least. There should be a heroes or heroines suitable for each and every one's liking out there, and (as with all aspects of spirituality), I do believe the choice of objects of worship or veneration should be deeply personal. Due to the wonder that is 'merchandising', building a personal 'heroon' for a modern day hero should be easy, should one wish to take worship that far.
There is one obvious benefit in using characters from popular culture: we know them. We know what they are like, what they have done, what they look like. We can relate to them. With characters from other times and cultures we're always guessing. The images handed down through the ages are generic at best. The true meaning of symbols has been lost, or, lacking the right cultural background, misunderstood. Adapting them to our own modern existence is always a little bit forced. (As a practical note, the fact that characters in modern media have a strong visual presence is also helpful for visualising them during rituals.)
Similar ideas are of course present in Chaos Magick texts, which generally advocate the use of any spiritual system or entity, regardless of origin. Many have a particular interest in popular culture. The Cthulhu mythos seems to be a particular favourite, though its deities obviously aren't 'heroes'. But other examples exist as well. Phil Hine, in Oven-Ready Chaos, relates the story of a colleague who invoked Mr. Spock to aid him in a computer exam (and got an 'A').
All of this, of course, hinges somewhat on the notion that spirituality and magick should not be all serious. There is a degree of absurdity in praying to a character from a TV show. But deep down, we all want to believe in such characters, don't we?