I've had the Insight for almost 10,000 miles now!
Looking at the dealer records, I saw no mention of a transmission fluid change, so I ran to the local stealership and picked up 2 quarts of Honda MTF at $10 each. The Insight's tranny only holds ~1.5qt so I have some left over, not sure what to do with it.
Tools gathered (sans funnel):
Remove the driver side front aero panel. Fill bolt is on the top and drain bolt is on the bottom (duh). Drain bolt can be undone with a 3/8" socket drive, fill bolt is a 17mm. Torque is 29ft/lbs and 33ft/lbs respectively.
I didn't need the hammer, bolts came right out. Make sure when filling the car that it isn't jacked up, on ramps or otherwise not level. Easiest way is to get a funnel with a hose on the end.
Total time for drain and fill was about 20 minutes. Subjective evalution: downshifting is slightly easier. Dropping from 3rd to 2nd at speed has a lot less resistance now. Highly recommended if your Insight is getting up there in miles and hasn't ever had a change.