I just went through the same purchase decision as you. I have a functional laptop so I don't _need_ to upgrade right away; I'm just at the stage where it's time to start looking. I did a lot of research on the Calpella platform and I'm certain the new 410's are going to be very nice, but the HUGE discounts on the T400 won the day.
I was absolutely SHOCKED at how little a T400 can be gotten for right now (for comparison, I paid around $2500 for my last Thinkpad, a T60p (

I miss IPS)). You can be quite certain a T410 with discrete graphics is going to enter the market at a much higher price point than today's T400. The only way these prices are possible is if Lenovo is purging inventory in preparation for the new platform.
My recommendation is to jump on the current deals. You'll only be missing out on maybe a 20-30% performance bump, but spending around half the money.
2764CT CONFIGURED SYSTEM
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