Thanks for all the suggestions girls!

I saw my GP last week (for me, not Lucy) and we weighed her while I was there. She's only 5.75 kgs, which means her weight gain has slowed down a lot. However, my GP asked me if she seemed happy, alert, active, was she still sleeping well. To all of which the answer is yes, in fact, as far as the sleeping goes she's extended herself by another hour until 5 am or later in the mornings (last feed at around 7-7:30 pm). So there's no need to introduce solids at this point, 'cause she certainly isn't hungry. She's still having up to 8 feeds a day as well.

The point about getting teeth and losing the tongue thrust reflex is a good one. Just a question, how can I tell if she's lost the tongue thrust reflex without actually feeding her solids?