DL does too, but only if you're logged in, and only on during the purchase process. Once you buy the ticket the info is lost. (oops, Steve beat me to it. Steve Holt!)

Of course you can usually estimate pretty closely from gcmap distances etc. and appropriate bonuses but that doesn't help in cases where what DL's web site says you should earn differs from what DL's IT thinks you should earn.

UA has an item on upcoming itineraries called "accruals for this trip" where you can look this info up post-purchase, although it is not without glitches either.