the simple answer to your question is no! 1080p is more than double the pixels of 720p therefore that 1080p video would be clearer and sharper but not necessarily brighter
all tv broadcasts are 24 to 30 fps maximum! youtube also caps videos at 30 fps no matter how many fps they were recorded in
Higher fps will produce a smoother image and if you want to use slow mo or really fast action ie. car racing then i would consider the 720p 60 fps but your image quality will not be clearer brighter or sharper than the 1080p. only smoother
^-- I agree with this answer. I believe the picture quality difference between 1080p and 720p is certainly noticeable, but not hugely so. i.e. IMHO 480 to 720 image improvement is very significant, 720 to 1080 is 1/4 more significant. 90% of my subjects don't offer enough additional detail to show the difference in the 1080 vs 720 recording (I'm just an amateur enthusiast, a pro would do better). I do most of my filming at 720, primarily because it requires less storage on the camera and therefore I get longer record times and it's less taxing on my edit software. However if it's my daughter's wedding, I would do it at 1080p!
b4u made an important point; what are you filming? If it's a car race or equivalent fast action where playback smoothness is important but detail less so, go 720p. But if you are filming people close-up or beautiful scenery or gardens with lots of detail, go 1080. Also, camera lens quality, CCD sensor quality, lighting, camera shake, composure, etc. all contribute to the quality of the final product. 1080p can't make a bad shot look good. Terb has some serious camera wizards, hopefully they contribute more detail.
In regards to "taxing" the camcorder, if the CCD or lens is of poorer quality, 1080 may show more imperfections. I've not really played with this, so can't speak further.