Would the Diecimila be Appropriate

To replace the controller used in this project: http://derbytimer.com/diy/

It would need to be able to time from a start signal to the tripping of each of 6 lanes (sensors) to an accuracy of at least 0.001 secs, preferably 0.0001 secs.

Need to know if it's plausible before I get in over my head.

Not sure. The chip on the Arduino only has two external interrupts, and you might want one for each lane to get that kind of accuracy. Not really sure though. Other than that, it would be okay: you'd need to do some low-level coding, but you'd have to do that with any microcontroller (and with the Arduino at least you'd get a nicer high-level interface for some things).

I think you should be able to use the "pin change" interrupt to detect state changes
on any input pin, sorta separate from the two "external interrupts."

BillW

Thanks for the answers.

My main problem is that I have scripting and programming experience, but no micro-controller experience.

The design at DerbyTimer lacks some features I would like to see developed, but I am unsure what would be the least painful, but hopefully feasible, way to duplicate the functionality of that design and then develop it more.

The board seems to lack the required number of I/O to implement the &-segment displays as the DerbyTimer does, but I figured that could be worked around by using a de/multiplexer.

Even if I were to get more into the lower level programming of the controller, the Diecimila board does look like a nice platform to start with.

Sorry for poor chip, terminology. My IC experience dates back quite a few years.