First off, XBOX Nation is a very good mag. Secondly, it is not an official mouthpiece. I read almost all of the mags on the market (except Gamenow) . . . sometimes the official ones (Nintendo Power, OPM, OXM) have decent articles and info. The unofficial ones are usually better in their reporting--I prefer Game Informer of EGM. Thirdly, these free subs are kinda hit or miss . . . when you pay for a sub from the publisher you will get it in a month, when you pay through a broker you will get it in two months (I paid $5 for Xbox Nation for instance), and when it is free you will get it in three months (50-50 if you are lucky). Hopefully, I can add a year through this promo 8)
I have gotten a lot of free subs, but not nearly all of the ones that I've signed up for . . . the reason they are free is that publishers need to have higher numbers and giving out some freebies bumps them up. Plus, they hope to spread word-of-mouth and maybe even hook you.
My bro had a sub to the Official Playstation Mag--I thought i was dumb . . . he gave me the issues and demos when he was done . . . I got hooked.