argg... I just had a long reply in here and it gotten eaten by the internet. So here is the short(er) version:

* don't try anything new on race day. this includes prep, nutrition, gear, EVERYTHING -- so try out things now and find what works for you
* nutrition is very personal, so you really need to try different things and find what makes your body happiest

What has worked for me for breakfast is oatmeal or pb&honey on a bagel. Sometimes half a bagel and the oatmeal. Depends on the race distance. Some OJ with it.

I tend to eat breakfast about 2 hours before the race I think. I don't really plan how far before it I eat, but more let the schedule determine it (based on when I have to leave for the race, how early I need ot get there, etc). But I have found this not to matter too much for me.

I've never done an olympic (yet) so I'll leave that one for others :)

I read in several books/articles and heard in a podcast that, while nutrition is very personal, you shoudl consume abotu 200 calroies per hour between the breakfast and the event. Also, if it's a lonegr race (70.3-IM) don't go easy on the salt.
Then again, this is not from experience, since I am a newbie.
Nayo
P.S: DO NOT eat anythign spicy (I'll personally vouch for that tip)

About 2 hours before the race I usually eat a bagel or two with some juice (usually apple). I also have at least 2 pieces of fruit as the race approaches. As for gels, I usually have one gel right when I get on the bike, but for OLY distance I don't usually need to eat much more. Towards the end of the bike I may have another gel, but it all depends on how I'm feeling in the race.

Our team coach gave us a good pretty good run down on nutruiton (oly and sprint) and I'll pass what I learned on to you. If you want to eat a full meal before a race there is nothing wrong with it but you need alteast 3 hours prior, but you shouldn't sacrifice sleep to fit in that meal. So if you can't eat 3 hours prior then grab a gel 10 minutes before you start. Both of these help keep your ah damn this is the part where I stoped taking notes, but basically it keeps your energy system from being all haywire. The gel 10 minutes before actually will keep your heart rate down a bit in the start of the race since your digesting the gel (and this can be a good thing, depends on the athlete), while the full meal 3 hours before will be cleared and just added to your base fuel levels. A meal inbetween will actually lower your natural fuel reserves, can give you a upset stomach, and depending on when you eat can keep your heart rate down more so then gel at the 10 minute mark. With all that being said, absolutely nothing wrong racing on a empty stomach, I was forced to do it at my last Oly tri and had 0 problems. You just have to have your nutrution up to par.

Changed my breakfast choice a while a go.

I now go with Cliffbar + accelerade bottle.

But am guessing I would add something else for anything longer than an Oly.