Coming from the daycare side of things (I've worked in this daycare for 2 years, mostly in the infant room). We do generally start inquiring about starting solids around 6 months or so. At this time it seems that the infants are starting to notice their surroundings and, for better or worse, are noticing that other infants are eating foods and they want a part of that! Most parents choose to bring a box of cereal and they basically tell us "do your thing". When that happens we start with feeding cereal once a day (around 11 or noon). By the time they are about 9 months old, most babies are eating breakfast (8am), lunch (11am), and snack (3pm). They all continue to eat bottles between (by that age the bottles are usually every 3-4 hours). It usually works out that they get breakfast at 8, bottle at 9:30, lunch at 11, bottle at 12:30, snack at 3, bottle at 4. Solids do not replace the bottle at all at that age, they simply are something for the babies to experiment with.
Steph, DH Jason (1-1-11), DS Owen (10-3-03) and DS Kai (10-13-11)