I'm wanting to go to FASM since I have heard so much good about it, but I was wondering what major differences were they between FASM & NASM which is the one I learned to use when I 1st started assembly? Could someone familiar with both break it down for me, major differences that is? Thanks, cheers to ashley for his help over at programmers heaven!

Well, FASM syntax is pretty close to the NASM one. Especially for instructions.
Actually if the sorce doesn't use macroses, NASM sources can be compiled with FASM and vice versa.
FASM have preprocessor directives and macro language, that is different from that in NASM. You can read about it here: http://flatassembler.net/docs.php?article=manual#2.3

Also it is a good idea to read about supported file formats: http://flatassembler.net/docs.php?article=manual#2.4

Regards