Becky 2005 - My daughter was 20lbs at 5.5 months (and that was only 2.5 yrs. ago), so we had to buy an infant convertible seat - rear facing at 20 lbs., this is the kind of car seat that you needed to buy. You didn't need to face your daughter front facing at 20lbs, as convertible car seats are available. Most kids are 20lbs, way before one year old, so that is why understanding car seat safety is most important - it seems that a lot of you don't know about convertible car seats, as you are all saying you had no choice but to turn your infants front facing as they outgrew their seats - that is incorrect, what you needed to do was go out and purchase the right car seat to fit your child's developmental stage, and that would be a convertible (infants/toddlers). As well, there are harnessed second stage boosters that are front facing that go to 47lbs, and not many parents know about these either, so they have 35lb kids in regular vehicle seat belts with a booster (in my province the law states that you must be harnessed until 40lbs.)
I guess it makes me sad that there is so much confusion and misinformation about car seat safety - most of this, I am afraid is the fault of the government though. In your country you have it even worse as each state has their own car seat safety rules as well.
Tiger