DS could never tolerate cereal. I never gave it to him and asked that it not be fed to him (but of couse, what did I know as a 1st time mom... sigh). My parents (who provide his day care) gave him it a few times and without fail it made him sick. Constipated, bloated, irritable - just yuck. So, after miserable baby and a daughter that threatened to quit her job so they would stop poisoning her child (yes, I got dramatic) they stopped. He is now a year and only recently started having cereal in other things, like the YoBaby yogurt cereal blend.
Most of the cereals are loaded with a ton of nasty crud that a BFed baby does NOT need, and ugh - there ae much better things to feed. DS did start solids a little early (he did everything a little early so far), but it was little bits of fruit every once in a while.