I got the same problem too...that hesitation in between shifting from 2nd to 3rd. It's a split second but when it shifts the car lurches forward like crazy.
To get rid of this, I turn on the ECT PWR button. I haven't gotten this problem ever with this on. To test, I turned the button "off" and the next day the hesitation problem came back. Turning it back on and it hasn't come back. Extremely weird and disconcerting considering this is a Lexus and the transmission is supposed to one of the selling points of owning a Lexus (i.e., the smoothness of its shifts).
P.S. I have about 9300 miles on the car.
[This message has been edited by laughingboy (edited September 11, 2000).]