Ahh, I found a pin sized hole under the slide behind G button. Also if you open the slide, and use your phone that it turns on the light you will notice light inside the micro usb connector. I am not sure if this means that dust can pass through it also.
Will post pic of said pinhole later when it gets a little dark here. Will try blowing in some baby powder into that hole to see if it does get into the screen.
EDIT: Pics of pinhole behind G button at the back of the slide.
Photo of phone with LCD on. Noticed the pinhole with some light showing thru and the micro usb connector showing some light.
Photo of the phone with display off.
EDIT: I might bring to T-Mo store for replacement but not giving up on this phone. Goodluck with the Samsung S.