I think GnR are one of the biggest bands in the word, even today. Their Greatest hits album was in the annual top 10 sellers in most european countries, beating the likes of Usher and Marron 5. GnR are still massive. Even appetite frequently pops into top 40 album charts across europe despite being 18 years old.
Take the net.. i really dont think there is a single band that out do GnR on popularity either. On ebay, GnR are one of the most collectable and searched.
Look at the media. They feature in virtually every issue of every magazine here in the UK. Every month Classic rock looks for an excuse to write about them.
Velvet Revolvers success has stemmed mainly from their media attension. But imagine how greatly discussed the new GnR album will be?! GnR have sold over 100 million records.. I think Chinese Democracy could add 30 to that.