According to an interview with Sci-Fi Wire, producer Ron Moore had this to say regarding the final season of the most-excellent series:
"The plan is to bring us to a definitive conclusion. There's no plans or thoughts in our heads, really, of then doing a follow-up feature or any series or anything beyond that."
Now having said that, they don't intend on tying up every single character story with a pretty bow...
"I don't know if we'll resolve every single thing about every relationship, and I think there's value in leaving some things open to the imagination and having some things that are sort of tantalizingly unresolved. But the intention is to move towards what is the final chapter."
Depending on what they leave unresolved, I'm really happy to hear that they want to definitively close the series. As I stated here, that's the advantage of knowing in advance how long a TV series will run - the entire story arc can be planned.
I'm looking forward to the rest of the series. There will be a two hour movie in November, and the regular series will return in 2008.
Source: Sci-Fi Wire