Although I haven't picked one up in years, I loved reading the Tintin comic book stories, which are a very cool mix of adventure and comedy featuring some wacky and memorable characters. There's no question about the talent behind the adaptations - Jackson and Spielberg are both high on a lot of people's 'best directors working' list, and their track records suggest that they are absolutely right for this sort of material (though Spielberg hasn't made a genuine adventure film in a while, so we'll have to see how the new Indy movie fares).
Most interesting is the fact that they're going for realistic CGI animation:
"They look exactly like real people -- but real Herge people".
This seems perfect - the comic itself, while having distinctive looking characters also had a realistic style to it, and a realistic style of CGI animation is probably as close to live action as it can get while still maintaining the visual idiosyncrasies of the characters. They could have of course opted for traditional animation, but that style doesn't seem suited to the type of visuals in a Tintin comic - the realistic look is bland in motion. A lot will ultimately depend on how good the final animation is, and it'll probably be ages before we see any of it (though animation tests have already been done according to the article).
In fact, it'll probably be at least a couple of years before we see the first film released; it's early days yet. It's pretty much a sure thing that with these names behind it, the films will come about and not languish in development hell. I can't help but look forward to these films already! Plus - Spielberg and Jackson working together?!? Thundering Typhoons indeed!