Lens choice for EOS 40D

[ssj1]

Hello folks, I just joined this forum today - sparked by my renewed enthusiasm :thumbsup: thanks to the impending release of the EOS 40D.

I have preordered the Canon EOS 40D from Amazon. I chose the kit with the 28-135 IS lens. I can spend about $1500 on lenses. The weight of the lens is an important issue. What is the best lens combination for my situation. I take picture of my kids, nature, landscape -general prosumer photography. I wanted to add the Canon 100-400 L IS USM to the kit lens. Any comments or other suggestions?

I know this is a question that has been addressed a million times , but the answers are never satisfying because no three people agree on the "perfect" combination. Will the kit lens allow good portraits? Also, I definitely want to stay with two lenses only.

Thanks,
ssj