VoU, I had a bit of an advantage, in that hou e-mailed me the 4000 BC save before telling me about the thread he started (Noble, Epic, btw).
Toranth, I played around a little bit with that very dilemma. The scout finishes in 8 turns, and you research fishing in 9, with the city growing in 17 turns if you work the plains wheat. Working the same tile, the worker would finish in 18 turns. I think the metric is how fast each gets you to mine/fishing boats/size 2, since from there it's a no-brainer to work the mine and boats for good production, +3f growth and a research powerhouse, and how much extra you can squeeze out before then.
Fishing boat first gives you the worker at turn 33 (8 turn scout, one turn into warrior or whatever while fishing finishes, then 12 turns on the boat and 12 on the worker) and the mine at turn 40. You can start working the mine immediately, for a 7f/5h/18c town.
Worker first gets the mine up and running at turn 25, but in order to grow, you'll be unable to work it for several turns. If you start the work boat at turn 19, you've got 45 hammers and 33 food to go and 6 turns of no improvements. In those six turns, you can accumulate from your one citizen 12 beakers/12 hammers by working the gold, 6 food/12 hammers by working a plains forest or 12 food/6 hammers by working the wheat. Once the mine is up (and assuming you begin working it right away), the work boat will either take 7 or 8 turns, depending on what you worked (5 hpt, 33 or 39 to go). That gives you the mine and fishing boats at turn 32/33. Working the boats to get to size 2 will take 5, 6 or 7 turns, giving you pop 2 at turn 38 for wheat and forest or 39 for the gold. Either way, you're slightly ahead of the boat-first method, and you've gotten 7-8 turns of +6 commerce in the meantime. I think worker first is the way to go, unless I've overlooked something or confused myself trying to run through all of this in my head.