Okay. So. New sets appear to be slight artistic deviations of a number of older, and newer, popular sets. We have Tahu Mata, Gresh, a Skrall, a yellow Rahkshi, a strangely silver Takanuva, and an un-mutated Vezok. This is an unexpected turn of events, for me, at least, coupled with Greg's assurance that next year we would be informed of Mata Nui's grand purpose. This has caused a number of theories to pop up in my head, and in the heads of others I work with. A few of those theories:

 

1. 2010 is a flashback year, possibly told by Mata Nui. To celebrate 10 years of Bionicle, and to pave the way for the new story, the team has decided to essentially recap all events up to current date. This explains the old-school characters, some in untransformed state, and the golden pieces, which are part of the special event.

Cons: Doesn't explain the yellow Rahkshi or the silver Takanuva. Silver Takanuva could be a representation of the half-shadow Toa who came to the Nuva's assistance in Karda Nui, but I'm not convinced of that.

2. 2010 takes place in an alternate universe(s). This explains the old-school characters and variations of known characters. Things are different, but not so different that they are unrecognizable. The easiest foil for this story would be the reality-jumping Vezon. This would help to explain Mata Nui's purpose, as it would be simple for him to slide into a universe where that purpose has been achieved/is in the process of being achieved, and for some helpful bystander to explain or for the madman to simply see for himself. This is by far my favorite theory.

Cons: If the story does indeed follow Vezon's random jumping, which is the easiest way to handle this theory, then why isn't he a set himself? Maybe he is, and we haven't seen him yet, but I'd think there would be some indication. Also doesn't sound like the way LEGO normally sets up the main storyline.

3. Time travel. This is really far out there, as even Greg has denied that time travel exists, but it must be mentioned here. I think the cons are obvious. And if that has to be mentioned, then also must be mentioned the possibility of...

4. A backup universe. Why leave things to chance, weigh everything on just one unit? Wouldn't it make sense to create a backup system, or simply a copy? Perhaps Mata Nui encounters this doppleganger, and goes inside to recruit the oddly familiar otherworld inhabitants in his fight against Teridax.

Cons: Too complicated.

5. The silver Takanuva is the alternate-reality shadow Takanuva that escaped Destral's destruction. This interesting chap was entertaining the possibility of destroying the universe when he waltzed away into the night, and I've always been wondering what he's been up to. No cons, as such, as it's really a long shot anyways.

6. The yellow Rahkshi is not simply a remake of the 03 baddies, but a character in his/her/its own right, i.e. a shadow kraata. Matoran/Toa/Turaga-level intelligence, superb control over its powers, fully capable of speech, the works. Again, not really many cons to this as it's more a personal wish than a theory.

7. It really is a flashback/recap and set inconsistencies can be explained away by the fact that they're prototypes. The finished product will be very, very different. This is very likely.