It has been rumoured that Willow will revert to witchcraft to bring Tara back from the dead.
This is unlikely, one of the major rules for witches is thou shall do no harm, and if you do you then suffer the consequences. Not only that, Tara did not suffer a mystical death, so if she was to brought back, would she be the same? I think not.
[Till Death Brings Us Together]
Buffy and Spike rekindle their relationship.
Okay this is a broad statement. Now that spike has a soul there is a possibility that there will be romatic feelings there on both sides, any idiot can draw that conclusion from the previous two seasons. However there is a lot of bad blood between the two, more so after the attempted rape at the end of the last season. So I am doubtful this will happen, although, again, I have heard nothing to the contray, I just don't wan to get peoples hopes up over wispers in the back corners of the internet.
[And then.... I Woke Up]
Buffy was actually in the mental institution and the whole of slayer-verse was a hilusonation. The Series is ended by Buffy comming out of catitonia...
All i have to say to this is hummmmmm....