Of course, now that Season 4 of The Office is over, we are free to speculate about Season 5! Hooray! It's a good time to do so, as there are pretty much no spoilers out about S5 (other than the fact that Steve Carell is writing an episode, and there's a spin-off that begins after the Super Bowl). So, vamos, eh?
Issues:
Michael / Holly / Jan
I hope hope hope hope Holly will stick around, I love her. Jan's baby isn't a surrogate's, though I'm not sure if it's Michael's or, like, Hunter's, and how that will end up coming out. This relationship won't be resolved entirely during the season. I'm very interested to see how this plays out, because while I now fully believe Michael and Holly are destined to be ;), Jan is no Roy/Karen, plus it's not like Michael to just abandon a pregnant woman. I think Michael will become a little more Michael-y around Holly. This is a woman that made a joke about an orgy, she can handle a "that's what she said." Kevin will make a major move on Holly ;)
JAM
It makes no sense to have Jim not propose before Pam leaves for NY. If the writers don't have that happen, it'll only be to create artificial tension and then I'll be pissed. If the season begins with Pam saying, "oh, yeah, I thought Jim wasn't really committed, so we kind of broke up over the summer..." I'll fucking throw something. I'll also throw something if Pam meets "a cute artsy guy that opens up her eyes to how life really is" or some shit. I'm terrified the writers will break them up over the summer, but if they're not broken up and they're not engaged when they come back, they'll be engaged by the end of the fourth hour-long episode. Also, something keeps nagging me about the fact that Pam didn't see when her art school started. Maybe we'll find out she accidentally applied to be in the class of 2085? Or something will come up and she won't be able to go?
Dwangelandy
Phyllis will hold the Dwangela liaison over Angela's head for a while to gain "political control" over the Party-Planning Committee (see my post on "Goodbye, Toby"). Part of the way through the season, and not through Phyllis, Andy will find out about what happened (I wanna see some Andy wedding planning :D!), and be heartbroken but get over it really quickly. Dwangela will get back together...in secret, of course. And, hopefully, we'll all learn what happened between Andy's proposal and the tag.
Ryan Issues
The stock of Dunder-Mifflin will probably plummet after the scandal, so maybe there'll be downsizing worries again. As far as people taking over Ryan's job, maybe Karen? She won't cause JAM issues this time. She'll be like, Jan before she went crazy. It could work; Rashida's other show got cancelled. Maybe Jim will get it, which would work on various levels, but... they already took Jim out of the office before. It'd just be a rehashing of that story line. Maybe it'll be a totally new character? Ryan is not gone for good. Steve Carell's episode with jury duty or whatever might have to do with Ryan's trial. Oh, God, imagine if all his former Scranton co-workers would have to testify... I think, between Kelly and Jim, they'd have to put him in jail for life! Though, Michael would give a hilariously positive review...
Darryl/Kelly
We'll just get little moments. Kelly will break up with Darryl for good if Ryan comes back into the picture.
Spin-Off
I do not think it will be any of the following:
1. Jim 'n' Pam 'n' luv 'n' NY
2. Ryan in jail
3. Toby in Costa Rica
4. except for maybe Andy, something that has anything to do with the characters we know now.
I'd still love to see Andy & Here Comes Treble touring cross-country ;) but I doubt that will happen. The thing that would make the most sense would be for them to cover another branch or Corporate, but I don't see how that could be all that different from the original Office. But... I really don't think the spin-off is going to involve characters we know already (again, except for maybe Andy, looking for love and a perfect rhythm section).
Hmm. Of course, I'll be back with more thoughts as more spoilers trickle in (soon, please!).