I was able to sit in on a session this year and I so listened to Stephen Downes talk about PLEs. I've been following Stephen for a couple years and so it was a pleasure and honor to not only hear him speak, but to sit on a panel discussion with him (I'll cover more on the panel discussion in another post).
But reading The Bamboo Project blog reminded of how our digital lives are spread all over, and the idea of a PLE is quite compelling. Michele's post My Personal Learning Environment is GREAT! If you are new to the whole idea of PLEs then you should check out a PLE in action.
I know Stephen mentioned that a PLE doesn't actually exist yet, and I would only agree in that a single PLE tool does not exist yet. However, all of the tools we use combined make up our PLEs and they will change and be dynamic over time.