I have 3 days (plus two half days, arriving in the afternoon and leaving mid day) to spend in Kyoto and surrounding area and am trying to make the most of it. Would it be better to stay in Kyoto or spend one day (and night) in Nara? What about Hakone-jo, is it worth the trip out from Kyoto? I will be travelling with my partner and we have rail passes so we do not have to worry about the cost of rail journeys.
The focus for the journey is the old Japan, temples, sights, architecture etc.
We did a day trip from Kyoto to Nara and it was quite achievable. I don't really see a need to spend a night there as it was a comfortable trip within a day. My blog entry about those few days over here.
Kyoto does have so much to offer that we probably could also have easily filled up our time just being in Kyoto. In fact, if I ever get back to Japan, I'd almost certainly allow some more extended time in Kyoto.
I'd suggest you can just decide when you are in Kyoto. If you feel you've seen enough, then take the trip to Nara for the day 
If not, just keep on wandering around Nara Kyoto.
[ Edit: Edited on 22-Apr-2013, at 01:23 by Peter ]
Hi, I'm in Kyoto at the moment and think that there is enough to see here to occupy you're whole time, especially if you're interested in temples etc. Consider staying by the station (I'm in a great hostel recently opened called Piece Hostel that is minutes away from the station) and you can hop on a train if the feeling takes you. Also, there is a lot to do in Kyoto at night e.g. wander the streets of Gion. If you're looking for cheap eats while you're here, I've managed to find food for under $5. Details are on my blog if you're interested: http://indianajo.com/2013/04/finding-cheap-food-in-kyoto.html
Not sure which time of year you will be here, but might be worth determining your itinerary based on the weather. It's still rainy at the moment and we took a day trip to Hiroshima when it was grey (felt like a grey day thing to do) and waited until it was sunny to see the Golden Pavilion, which looked stunning in the sun.
Hope you have a great trip. Kyoto is amazing.
I did a day and night in Nara and really liked it. Nara Park is great in Autumn when the leaves are changing. And feeding the dears is so cute. And if memory serves is where the giant buddha is. Stayed in a nice Ryokan a couple minutes walk from train station. And the town itself seemed relatively chilled. Still found stuff to do though. All in all I would recommend it.