I am NOT a nutritional expert - this is just my two cents from personal experience. (If anyone in the Mad Cows is an expert or has other tips, please jump into the conversation here!)

Most importantly no matter what, from what I've read, the key is to experiment early in the season to find out what works best for you. A couple of suggestions that I've tried that worked for me in experimenting.

Again, totally personal for everyone:

* Early season spin classes and swims are good for checking your body's response to new stuff.   (Bathrooms are nearby in case something isn't agreeing with you!)

* Start with a little bit of whatever you are trying and increase over multiple sessions (Hammer, Infinit, Gu, FRS, Gatorade, Chomps, etc.)

* Get opinions and figure what works best for you.  For example, I discovered that the "Caffe Latte" flavor of Hammer's Perpetuem gives me gastro problems, but the Unflavored and Orange Creme are just fine.  I can consume Clif Bars easily, but PowerBars don't go down so easily.  Again - this is totally personal for everyone.

* I happen to have an iron stomach with solid food pre-race.  I ate a Denny's Grand Slam then ran a Half-marathon PR in 2009.  Some people are like this, others aren't.  (Great for fuel if you are!)

* Read, read, read - lots of articles - you need to sift the good articles from propaganda.

Good article on Beginner Triathlete about bloating:

Nutrition for Newbies:

Most of all, do your homework and be willing to spend a few bucks for enhanced nutrition.  Some of these races are $200+ to enter not to mention all of the time training.  Nothing worse than having GI (gastro-intestinal) problems or bonking on the race course.

Happy Training/Eating!