same problem here.. the only difference is that my songs are from itunes and when i use them on serato i have to analyze them one by one. it sucks.. i hope someone can tell us how to analyze BPM all at once

I don't think we have the same issues, becuase Serato will auto calculate all files on it's own without you having to load one file at a time, see here for detailed instructions:
serato.com

I was simply looking into if Serato would recognize the BPM's for my library which already has that info, for example, when I import my tracks into Virtual DJ, the BPM's show so no need to re-analyze.

This is happening to me to if anyone knows of a salutation to this problem please post a reply

Are you analysing within SDJ?
Is there any reason to bother doing it externally when you want to analyse within SDJ to get your overviews etc built?