I do agree that goths and metalheads are often lumped together or confused for one another. If you wear more black than most others, keep to yourself, and listen to "different" music you're probably going to be labeled a goth by the general public. "Mallgoths" are most easily recognizable though. But they usually don't listen to any goth music though, instead groups like NIN, Slipknot, Tool and some metal and rock bands. This is also where I think some of the confusion comes from.
Gothic rock is really a long-dead genre except for bands today who are clones of The Sisters of Mercy, Christian Death or Fields of the Nephilim. And there's just too many of these.
However, you can argue that it has evolved or perhaps been replaced with a "dark" music scene. Music today that is being labeled as goth or that appeals to goth audiences generally features less rock and synth, more ebm and electronics. I'm not as keen on the latter personally.
My personal favourites include London After Midnight, Suspiria, Radio Werewolf and Christian Death.
If you're interested in goth life, I'd really recommend watching this. It's awesome, great sense of humour.
[ame="http://www.youtube.com/watch?v=pKlH4XX-Wfc&feature=related"]http://www.youtube.com/watch?v=pKlH4XX-Wfc&feature=related[/ame]