Connecting panasonic plasma 42X30 to my laptop via hdmi, i can get a resolution of 1920x1080 on the plasma. When I first connected the TV, it switched my laptop display to 1280x720, but I could change it to 1920x1080 (my laptop has full hd display with ATI graphics). The 1080 resolution is stuck on the plasma and it displays "1080p/60Hz input" in the top left grey box/banner for 3 seconds.
Not sure how that works out, but i am guessing it gives me that resolution using 1080i because it is pathetic (very jagged) compared to smooth laptop 1080 display in much smaller screen and the text on the plasma is not clear enough - some lines of the text look deleted and some lines look stretched.
But its quite effective for watching movies played from laptop.
See pic of resolution selector: