You can soon expect to pick up a free song of your choice from iTunes with every concert ticket you buy at Ticketmaster. No gimmicks, no catches. Buy a concert ticket, get any track you want, gratis.
The other side of the promotion extends a program where last year, for example, pre-orders of Stadium Arcadium from iTunes got RHCP fans early access to tickets. By pre-ordering "select digital albums," you'll get a crack at that artist's tickets before the rest of the non-iTunes-using barbarians do. No word yet on which artists are participating, though...
Finally, later on this year, rather than buy separate gift cards from each, you'll be able to drop dime at Target on a single "Ticketmaster + iTunes gift card pack" that you can use at both Ticketmaster.com and iTunes.
All in all, it sounds like a great deal for iTunes and Ticketmaster customers, since there seem to be no strings attached. My only gripe is that as pricey as concert tickets have gotten, it feels like they should give you a whole album for free. Or several. It's also too bad I don't really go to concerts anymore, because this might actually get me to download tracks from iTunes beyond the free ones I got from Pepsi ages ago.