Update:
I've evaluated technologies for my online greenmap, have selected googlemaps as my mapping webservice, and opted to leversage an asp.net server-side map control as the interface. also, made a first stab at creating my icons in photoshop from the GreenMap icon font collection. So now to begin building the actual website. I should have an alpha version up and running by this time next week, although likely quite a simple implementation initially.
Consistent with my watershed organizational principle and a bioregional approach, I plan to start with what I'm most familiar with and select some intial watersheds within the Lake Washington basin that are more local to me then gradually add more content - and more geography - as the project progresses and as potentially more folks might become involved from other watersheds in the basin.
So stay tuned!