Right now, I have 1 8x8' raised bed that holds quite a few veges. Enough for the DH and I.
I have found with on-going back and neck problems, that I am doing far too much reaching and bending in ways I shouldn't be. I have put a brick walkway down the middle of it so I don't have to reach so much.
We are going to add several raised beds this year, but will be making them 4x8', so we only have to reach in about 2'.
We will be putting old carpet in the paths between the beds, then gravel on top of the carpet
I'm hoping I can figure out how to post pics by then! LOL
I don't recall if there is a square foot gardening forum on this place, but you might want to look that up.

Boondoggle,

hmm, heres my reasons to go with several beds:

If you just want to grow one or two veggies, a big bed would be ok. But if you are growing lots of stuff, having several beds makes it easier to rotate your crops and also gives you space to leave flowers/herbs undisturbed throughout the season.

If you have several beds, you can create them in a pattern where you have some pockets of shade for summer and pockets of sun for winter.

If you run into a soil problem with a bed, you can shut down that bed but not lose all of your growing space.

If you are planting other areas, you can easily section off a bed as a nursery bed to hold plants. This becomes especially handy if you hit a clearance sale!

Thanks, ninjabut, the reaching thing is a real issue with me. This Saturday DH and I dug up a portion of the new garden, and both our backs were complaining by the end of the day.

manzomecorvus, the plant-holding bed idea is a real winner, as I was wondering how to move my perreniels around while I "remodel". Now I know! Into the new bed they go, for now at least.

The soil-borne disease thing is important, too. It's one of the reasons I wanted some new beds. My tomatoes had blight last summer, and I realized that with my existing plan I had nowhere to rotate them this summer.

It's almost a forgone conclusion in favor of small beds. I just hate to lose all that space to paths.