We do get these announcements every couple years, but this one looks like it has some muscle behind it.
So much depends on the quality and the tone of the adaptation that it's pointless speculating right now.
Amber is a pretty great length for an adaptation. Yeah, the books are very short by modern standards, but that means you won't have to leave anything out.
I don't think they have anything in them that hopelessly dates them. Much is always made of the smoking in Zelazny's work, but that's just to give the characters something to do when they're talking. I think it can be excised without fundamentally altering the character of the books.
I'm not much for stunt casting, but a friend on Facebook suggested that Trent Zelazny play the role of Roger the guard in the Hand of Oberon. I think that's kind of brilliant.
I'll be thrilled if this happens and it's done well, but in the process of thinking about it, I've discovered that the TV adaptation I really want is an anthology series of Zelazny's short stories. We can open with Divine Madness!
And maybe that can serve as the gateway to the Roadmarks movie I want so much.