ran a few passes and i think it's a solid start, muddleglum.
haven't tested with a joystick yet (and i have a wheel-stick paddle-thingy controller i'm anxious to dig up and try as well) so re: mouse controls, i prefer (and can see a short learning curve using) the proportional mouse with cursor visible options. also, consider adding keyboard (only) controls?
re: the physics, seems more "arcade" vs "simulator" to me. if sim is what you're after i'd consider tweaking the friction on the rear wheels (there should be some more sliding at higher speeds). also, the turning radius seemed too "wide"/should be able to make tighter turns. if you're graduating them based on speed in the steering mechanics (for playability), the slower speeds should provide a tighter turning radius. i spun out a few times leaving me facing the wrong way; when trying to right my position, my u-turn was a bit wider than it should have been based on the car type (compact?), in my opinion. i don't know if that car could make a u-turn on a city street without climbing the curb/using the sidewalk, for example. or, you'd have to make a 3 point turn, etc.
also, seemed like suspension was very tight. atleast in the replays, there wasn't enough lean.
also, the route isn't quite obvious enough. an in-game mini-map or street signs with arrows directing the driver would help a lot! i know you provided a map of the route, but it's hard to see when the turns are approaching with the driving perspective you're using. i (somehow) completed a lap once, but don't know how i did it. heh.
the options interface needs a little work, too. i found that you had to hit R and then O while stopped to get into the options (lots of games allow you to enter options screens at any time so this was a bit confusing). from there, everything seemed to work (i was able to change set-ups) but there was no confirmation of the current set-up until you hit R again and began the "race". if you could highlight current choices within the options menu, it would help a lot vs the user/player wondering if the controls were set.
re: the replay feature and options, i loved them!
only suggestion would be to change to next camera a litle sooner (in the pan modes, the car seemed a LITTLE too far away before it switched to the next location). also, i wasn't able to save a replay. it made a "reply" file in the directory, but it was "empty". i don't know if you have this fully implemented in the current version, so...
overall, a great start! i look forward to this being fine-tuned toward master-piece status. speaking of which, your paintings are very nice, as are melody's miniatures! i can see you're very much into detail in whatever you create, so, no doubt, this sim will definitely become "art" as well!
edit: also, wanted to mention TORCS, if you're not already familiar with it. it's an open source "racing simulator" that i had looked into some time ago. you may find some useful info there regarding the application of "driving physics" for games.
http://torcs.sourceforge.net/
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