I got two 50-light strings of white lights from Plow & Hearth. They seemed to have the best price on what I wanted. When they arrived, I pulled them out of the box, let the solar panel charge for a day and then wrapped them on two plants in the front yard that grow in a bit of a cone shape.
When you set them up, you wrap your lights where you want them and then stake the small solar panel in the ground nearby.
So far, I'd say I'm fairly happy with them. The solar lights have a light sensor built in, so they turn on automatically when it gets dark. When they light up, they look nice--although not as bright as traditional plug in lights--and the solar battery life seems fairly long. They stay lit for around 4 hours.
The lights are nice, but not perfect. I have noticed two issues:
1) It takes some trial and error to find the perfect place to put the solar panel. I have had to move mine several times when the lights weren't sufficiently charged by the end of the day. And, of course, if you live in a place that actually gets gray and gloomy in the winter (as opposed to sunny Los Angeles), I'm not sure how well the panel would charge. Although, if you live somewhere with snow and sun, I imagine there would be enough reflection off the snow to charge the panel right up.
2) The light sensor is very sensitive. The street light across the street, our porch light and even my car headlights have caused the lights to turn off. I think I have the sensor turned in a way to minimize that problem, but it is a bit annoying. If you live out in the country, you wouldn't have this issue. But, in a place like Los Angeles, it's pretty hard to find a place that's completely dark.
Overall, though, I'm glad I got them. Because you don't have to plug the lights in anywhere, there are no annoying extension cords to deal with, and your light decorating options aren't limited to where your outlets are. Plus, they cost nothing to operate, and with their LED bulbs, they should last for many Christmases to come.