This was my same question when we started solids! I started about the same time as you...with rice cereal. My LO didn't like it as much and was spitting it out...so we waited a few weeks to see if she was ready again. What we did was feed her a cereal a week...just for breakfast.
I asked a pediatric dietitian about what to do next and she said that when you introduce the veggies, it's supposed to be in addition to the cereals. She also said that it is up to me whether to have lunch or dinner, but the most important thing was that they were getting a change to "practice" eating the foods each day so that they will eventually learn to eat more and eat a variety. So...she said do once a day but do veggie then cereal...we did this for about two weeks....and then we started introducing a new veggie and then doing a dinner time meal. The hard part for me is finding the good time to give dinner because I read you weren't supposed to give them food 2 hrs before bedtime...so their tummies are settled.
But....I think that the PP is right, you do what you feel is right for your LO, just make sure that they get enough milk first...my DH gave my LO solids BEFORE milk today and she only ate 2 oz!!! Good luck!