@Machomuu: Yeah... I'll point out that the the Sinnoh Pokedexs and above say nothing about Mew having the genes of all pokemon. This means that Gen 4 and 5 Pokemon may very well be exempt from that. The 'fact' that Mew has the genes of all pokemon has also not actually been proven. It's mere speculation based on it's ability to learn and utilize any move including transform. After all, how could they possibly know this for real, having never been able to catch a Mew? The fact that Mew is shown to be a weakling in the games is also evidence against it creating...anything really. Level 30? That's...like...bottom tier of legendaries right there.
If anything, I'd say that Mew is exactly what it's made out to be, a relic from the beginnings of time that hasn't evolved in god knows how long. Other pokemon may have even evolved from it, however there were definitely things before it. I think the issue with discrediting Arceus is that you can totally go to heaven and fight him... at level 80 wielding an insane BST, the ability to change to any type, an insane movepool, and the move /judgement/. It's not...exactly subtle.
One must note that it doesn't say that in the Pokedex, it says it in the notes in the Pokemon Mansion in Kanto, which takes place 2 years before Sinnoh, and also it says it in the Johto Dex in GSC and HGSS, which take place during the events of the Sinnoh region. Also, one must remember that the moves are simply names of the abilities that are shown in the Pokedex, it's never been stated, but more likely than no they are names created by those working on the pokedex to give trainers easy access to the abilities of pokemon. It's similar to training a dog to jump by telling go in the air by saying jump by saying "Jump". It follows Pavlov's theory that a word can mean anything, it's what it is in real-life that matters. For example, if you taught a Pikachu how to use what we know as "Thundershock" by saying "Rock Smash", it'll believe that "Rock Smash" means "Thundershock", because that's what it thinks it is. Coupled with the fact that many pray to Arceus as a God, it's no wonder the move is called Judgement, but chances are Arceus didn't name it that, humans did.
Also, about Mew being weak, I dunno about that. Sure, Mew is a low level, but that doesn't mean it's always been weak, there are several variables over the years that could have caused such a happening. But also, Mew can use every move. Now, let's say that the fur move limit didn't exist for a moment, as Pokemon is a game, and chances are that it exists simply because it's a game. Now, doesn't that mean Mew can use Spacial Rend, Roar of Time, and ultimately Judgment? Plus it can use moves like Wish, Draco Meteor, and Recover- it doesn't need to be strong stat-wise, it has enough to protect itself on its own, it has no real reason to be strong.
That's what I believe at least, but I do like the theory presented by RHCP. There is evidence to support that as well. In the Pokemon Mansion it clearly states that Mew was originally sighted in South America. Now, that may just sound like Nintendo not knowing what they're talking about, just screwing with us because they think we're stupid, but if you think about it, it does make sense (or rather, it can). What if originally the planet takes place on was just like the one will live in now, there were animals such as Humans and Mew. Then, X happened. Whatever X is, we don't know, but it destroyed (or ruined) reality as we know it, and eventually Arceus was created from an Egg, and thus things proceed as Bulbapedia states. Well, that's how it could be stated canonically at least, once could just believe Nintendo was screwing with us and could just go with the Bulbapedia entry. But having said all of that, I don't know why any God would bestow Mew with that sort of power if even he didn't have it. Of course, there's also Variable 1, the idea that a pokemon existed before Arceus, which isn't all that unlikely given Nintendo's attitude and mindset on adding Pokemon, they're bound to making "the creation story" incredibly convoluted. Anyway, I'll leave it to Nintendo to present the rest of the story. Or not.