Posting one of the first issues. I drive this 2004 GTP every 2 to 3 days. After the car sits for about 2 days, this condition occurs intermittently.

I believe the term for this is a garage shift. I put the car in reverse and back out of the driveway using no gas, just gravity and brakes usually. Then I put it in drive, press the accelerator and there is a hesitation. It only lasts a second or less and then the power kicks in. This is not a transmission delay, I have been experimenting and waiting until well after the shift has engaged. It seems like there is a brief fuel delivery problem after sitting idle for a few days.

Anyone drive the car intermittently and experiencing something like this? I have not taken it to the dealer for this yet, since it is very hard to reproduce and can only do so once every few days.

I haven't experienced that problem yet on mine. Had it just over a month now. Granted I don't leave mine sitting around for days without driving. Longest mine has been sitting is 1-2 days I believe.

I think I know what you are talking about... I have the same problem with mine... I'm not sure if it is a fuel delivery problem, but I think that it may be a transmission thing. Nothing to really worry about... have you tried:
1) Backing out of your garage, no gas, just gravity and your brakes
2) Putting the car in gear
3) Taking your foot off the gas and letting the car roll for a few feet
4) Pressing the gas

See if that does it. It may be the transmission doing something funky. Like I said, nothing to really worry about.

Is this an issue only on the supercharged engine?

You know, that is a possibility... my 04 is supercharged, but now that I think about it, my 01 GTP had sort of the same problem, too...

I do remember hearing a little transmission grind (in both cars) when I back out of my garage... I think it's associated with that. I took it to the dealership and they said it was common and there was nothing to worry about. Let me know what you think or find out.