Yeah, I thought about getting rid of Apache but I use mod_rewrite quite a lot, and I still couldn't figure out how to do the rewriting in Nginx. That's what holding me off.
I also did some researches about Nginx, Apache and PHP and found that Apache is faster than Nginx when it comes to PHP, but Nginx is light and a lot faster when it comes to static contents, so I thought why not to take advantages of both's strength.
But I do still need to do a LOT of homework to get the best results.
Thanks again, mate