After each release of Cincom Smalltalk, we have a set of planning meetings. I just spent a week in Santa Clara, with the entire Smalltalk engineering team. These meetings are compressed; we have a lot to talk about, and - relatively speaking, at least - very little time to talk. Our development staff is very widely spread out - we have staff in Santa Clara (office), Cincinnati (office), Oregon, southern California, Ontario, Illinois, New Hampshire, Germany, Pennsylvania, France, Japan, and India. I'm located in Maryland. What that all means is that our planning meetings are really the only chance to get the entire team in one room all at once. Sure, individual product area teams get together from time to time - but this is different.
We try to go over the just completed development cycle - so that we can see what mistakes we made, and how we can improve in the future. In my role as Product Manager, I lay out the product priorities going forward, and engineering, in turn, tells me what kind of progress towards those goals I can expect (based on existing work in progress, resources, difficulty, etc.). We also plan out the delivery schedule for the next release.
That all keeps us going for many hours over the course of 3 days. It's always a useful exercise, even if many of us come out of the process a little bit frazzled. The good thing is, we have the holiday season coming up, and many of us on the Smalltalk team have lots of days of vacation built up - so we have plenty of time to relax, refresh, and get re-invigorated for the next round of work coming up.