Windows 7 is a ground up rewrite of Vista... its a much better OS... though i haven't had any issues with Vista myself... it took a bit of getting used to thats all...
The experts are saying Windows 7 is the best Microsoft OS ever... it even runs on older machines, runs great on netbooks.
The biggest problem with Vista is public perception... everyone thinks because some says its bad that thats the truth... but to be prefectly honest with SP1, Vista is perfectly fine now...