I had some time today to play with my timeline again. You can see it here. I've figured out how to resize the bubbles so large images don't get cropped. I've managed to key the different types of events to different colors on the timeline. And I added a box that allows you to restrict certain types of events. If I wanted to specify more attributes for these events, I could bring in additional boxes as well.
I'm not happy about how the one "mixed" event is rendered in white against the light gray background. I've got an email out to the experts about controlling the color selection of both the timeline and the event types. I anticipate that their response might be for me to look at other examples source code (CTRL-U to the rescue), but while I've done that, I can't yet see how to implement this specific change.
I found another related tool today: The Universal Timeline Aggregator. This is basically a tool that takes an RSS or Atom feed and displays the information on a timeline. You can do it for this blog. But the low incidence of posting means that it isn't particularly exciting. I've tried it with more populated RSS feeds: CNN, The Valve, Go Fug Yourself. But they drop off surprisingly quickly. I'm not sure what that means--possibly that the Timeline Aggregator won't reach back past a certain point or that the feeds from these sites are restricted to be only so deep.
But you don't really come here to have problems solved, do you?