My question is.. It took me about 3 weeks to get the OK to have adsense on my website, I'm now working on a 2nd site, now I haven't looked into anything, but I'm very sure I cant apply anything from the one site to another, like via the same account (as in website) right? So that being if I have to apply for adsense for another site does it go any faster for your 2nd site or how does that work? Thanks.
You don't need to apply again for your second site. Once you are approved, you can put the adsense ads in as many sites as you can as long as those sites comply with Adsense TOS.
You can put AdSense ads with your publisher id in any sites/page you want. If you prefer, you can also list the sites in AdSense configuration page which will be used for adsense ads. However, you do so, you can still place adsense ads with your publisher ids in any page but you will not get any payment credit from clikcs from those non-listed sites, and AdWord advertisers don't have to pay for those clicks also.
This is one of the best features of adsense. I recently signed up for Kontera to test it out and I am highly annoyed by the fact they they have to manually approve each site I want to put it on. I own dozens of domains and it makes it hard to test which sites it is effective on.
I kind of wish Adsense would do this, too. A lot of people create a half-legit looking blog to get into the program and then out come the spammy MFAs once they are approved.