I would love it, and be surprised as hell if they are able to keep something like that out of the news (internet, etc.). Hope so!
I doubt they will cast Osborn(s) yet, since the storyline in ASM1 will not involve them. I think they will simply hint at the character and his counterpart.
I would LOVE to see an ending calling card or somesuch.. like a Pumkin Bomb left on Peter's stoop... or some police report where they question why witnesses report seeing a pumpkin bomb before the explosion/etc.
*similar to Batman Begins/Joker*
Marc Webb and the writers need to be mighty careful not to try and ape Nolan's Bat-trilogy too closely. I have no problem at all with them wanting to use Goblin as the villain in a second film. But I would hate if they do some kind of "calling card" scene at the end with Spiderman and say Capt Stacy.
What I would love is if they have already cast Norman Osburn and they have him pop in for maybe one scene in ASM. Like say he comes into the lab to talk to Connors and Peter is there, perhaps an exchange is had and nothing more. It would be a great way to introduce Norman and show that the filmmakers are thinking ahead.
I just find it odd if we don't see Norman in ASM. If Connors is a prominent scientist within Oscorp, he would have some interaction with the company's CEO. Norman has always been portrayed in the comics as someone who is very hands on when it comes to the day to day operations of his company. I would think he would be on the floor with his workers on a pretty regular basis. Especially for something as important as Connor's efforts to regrow limbs.
It would be a shame for the filmmakers to miss an opportunity to bring Norman in organically to this story. Again, just a cameo not a starring role.
As far as Gwen, her fate is sealed. There is no way that those involved with ASM will miss the opportunity to bring The Death of Gwen Stacy story to film. It is THE classic Spiderman story and one that is just so powerful if done correctly. True by killing her in the second film you risk comparisions to Rachel Dawes and The Dark Knight. But again, if done correctly, it won't matter.
The real risk here is that Sam Raimi did a scene similar in Spiderman with MJ. Marc Webb will have his work cut out for him to try and make a Goblin-Spiderman fight seem different than what we have seen before.
The other challenge with the whole Norman Osburn story is how do you bring Harry into the mix. Again they are competing against the Raimi films in trying to make their Harry different than the one previously portrayed. If there had been more time between the Raimi series of films and this new series, it would not be as difficult. But as it stands now, it will be awful hard to prevent the audience from having a been there-done that feeling when watching the Peter-Norman-Harry triangle.
For my money, here is what I would like to see:
ASM- Lizard with a Norman Osburn cameo
The Spectacular Spiderman (good title I would say)- Goblin and death of Gwen Stacy. Introduction of MJ as a friend of Peters
Spiderman no more (eh, all I could come up with)- Kingpin and Mysterio. Mj and Peter get together.
I really would love to see the filmmakers weave characters and threads through these films that are introduced and then paid off in future films. The Norman Osburn cameo being an excellent starting point.