Funny you should say that. The same thing happened to me. There's no hard science about what you should do. I decided to pinch mine out, I just planted them out and want them to get established and develop a good strong root system first. Now I'll let the tomatoes develop.

The fertilized flowers(these plants self fertilize) will become tomatoes. The unfertilized flowers will become tomatoes.

I would pinch them out so the strength goes into the plant until its bigger.

I agree. The tomatoes come out much nicer.