What makes difference between GM and SuperGM?

I just thinking, what's separate GM's to SuperGM? If GM rate is little bit over 2500, what he/she can do to reach 2700-2800 rate? It's must be very hard to progress anymore, if you rate is already so high. In principle GM already know "everything" on chess. How to make progress in GM level? Of course watch how SuperGM players play but is there something else what GM can do?

Super GMs are those GMs who get invited to a bunch of elite tournaments. It's not so much about the rating as the exposure to the very best players and the chess media.

Yeah, I would say 100+ or more rating points, plus, wins in elite tourneys, candidates matches and WCC matches separate the ordinary GM, from the elite GM...

Super Gm's are the elite the best of the best players in the world the world champion is King Kong of the mountain until someone knocks him off.

Sound like the difference between models and supermodels.

http://ratings.fide.com/top.phtml?list=men

The May 2013 FIDE TOP 100 rating list starts out at 2868 for #1 GM Carlsen down to #100 @ 2653. I'm not sure exactly what qualifies one to be a "Super GM" but I think being on this list is required for starters. Offhand I'd say all WCHs - with a few exceptions, like the FIDE WCHs when Kasparov was the real WCH - and everyone else who played in a WCH match qualifies for this title

In 1951 FIDE made 27 living players GMs inc a bunch of inactive  players who clearly deserved the title for past achievements. Now there's about 1400 GMs so another title seems to be called for

Perhaps, but "model" includes patzers like Paris Hilton, while "supermodel" includes Super-GMs like Cindy and Heidi, and a wide range of GMs, FMs and IMs.