I felt this would be a great thing to discuss on the Blog, as it's a lot easier to make strong connections and "theorize" with logic on here than on the wiki (where such connections, when not 100% proven, are not allowed on main articles). The opening scene with Pierre Chang is interesting as it appears a little out of context, prompting a few I've spoken to to suggest that it was merely there for Pierre fans or Comic Con supporters (see below). I, however, believe it to be integral to Season 5, and think we should take heed of this scene in particular.
Let's start, however, with what we already knew before Season 5 aired. The main thing I want to point you to is the 2008 Comic Con video. For those of you who missed it - basically Lost cast and crew host a special Q&A session every year at the Comic Convention is San Diego. In 2007, they played a cool video for us featuring some time travelling bunnies. It was also the first mention of an Orchid station. In 2008, a character of the then current Lost ARG, Dharma Initiative Recruiting Project (which was about as innovative as its title), filmed another Pierre Chang video being played. Amongst other things, this new video revealed the guy's true name. It also featured a character called Lara off-camera, a baby, and a guy behind the camera with a suspiciously familiar voice. Let's watch it again:
Further details about this video and where it came from can be found at the wiki Dharma booth video article, in case you missed the ARG over the summer. So now that we know this information, I'm going to compare it with what we know from Season 5. We saw Chang wake up with a woman - so it's probably not much of a stretch to assume she might be Lara (though the ABC press release helpfully credits the actress as playing "Woman"). Then we saw the baby, who we knew existed from the Comic Con video. I'll let you all speculate about who the baby might be in this crazy time messed up world... but my money is on Charlotte.
Furthermore, it seems pretty much proven now that the man behind the camera is none other than Daniel Faraday. Faraday was always the front runner because of the voice, and now with the opening S5 scene - we can all accept this chain of events. We can also somewhat explain why Faraday describes Chang's comments as "useless" in the video - as his speech in S5 about being unable to change the future would naturally make him cut-off Chang's pleas about us finding ways to change the timeline.
Lastly, we can gather that Faraday must make some form of contact with Chang in his time, and that he will tell him intimate details about the DHARMA Initiative's future (including that Chang will lose a hand judging by the way he cradles it).
So what will happen next? We can be sure to look forward to 1970s DHARMA scenes for sure - which personally I think is very exciting. What's even more interesting though is the possibilities it throws up - will it be Bernard who leaves a glass eye in the Arrow station? Will Faraday help build the sonic fence? Will Juliet and Sawyer be the Adam and Eve skeletons? With time relative, anything is possible!