As with most genres of music there's popular stuff that tends to appeal to younger or more casual listeners - radio metal is the term I use to think of it: Lamb Of God, Devildriver, Machine Head, Soil, Ill Nino, Killswitch Engage, almost any band on Roadrunner Records who you see proping up the first and second stage at Download.
Then if you're willing to dig a bit deeper there are some phenomenal bands out there at the moment, particularly in the doom, grind and black metal genres, though obviously these more abrasive styles require a bit more of the listener and tend to put off tourists (apart from the hipster types who just want to say they listen to the most brutal things going). Anaal Nathrakh, Witchsorrow, Dillinger Escape Plan and Terror are the first names to jump to mind doing great things at the moment and Napalm Death are still releasing brilliant albums 30 years down the line: Utilitarian was a cracking record.
So horses for courses really, if you want the more Metal Hammer/Kerrang friendly metal it's out there (I was enjoying a bit of Lamb Of God myself the other day), or if you want something heavier, more artistic, more interesting and dare I say it, better it's there too, but to suggest modern metal is irrelevant and lacking in quality is just daft.