It seems there is a misconception going around that SNK is not interested in a sequel to Capcom vs SNK 2 and that we need to somehow get in touch with them and convince them otherwise.
When in fact, in the past few interviews with SNK Playmore officials, they openly state that they are interested in working with Capcom again and even for a sequel to the SNK produced SNK vs Capcom: Chaos.
Following are excerpts and links of SNK higher ups showing considerable interest in sequels to CvS2 and SvC:
"Playstation Blog: We still miss SVC Chaos and Capcom vs SNK titles. Do you think we can see a new crossover with characters from both companies again?
Yamamoto: Crossover games not only provide excitement to fans, but to us developers as well, so I’m hoping we could do it again someday. In order to make that a reality, we’ll continue to do our best and make KOF bigger and better.’’
http://blog.us.playstation.com/2011/11/01/the-king-of-fighters-xiii-interview-fighting-its-way-back-to-the-throne/
"7. SPEKSNK.org: Crossovers are hot right now. Can we expect any with SNK PLAYMORE characters on it? I’m certain fighting games community wait anxiously for a new game crossing Capcom and SNK…
**KY:**As this is something very valuable and stimulating for us as well as the fans, I sincerely hope we will have the opportunity to participate in the development of a collaboration title sometime in the future. Therefore, I will continue to promote “KOF” so that this dream comes true.
"
http://www.speksnk.org/foro/viewtopic.php?f=23&t=74471
"SNK-Capcom.com: Besides SNK fans, CAPCOM fans have also been dying for a sequel to “SNK vs CAPCOM”. Do you have any plans to make a sequel to this game?
SNKP: We are sorry, but we can’t answer to this question. However, we know that this game is highly appreciated among fans, and that they’re waiting for a sequel. There are also many “SNK vs CAPCOM” fans at SNK PLAYMORE, and we also hear from people who want us to work in collaboration with other game companies as well. It is not impossible to see a sequel to “SNK vs CAPCOM” one day if fan requests keep getting bigger."
http://www.speksnk.org/foro/viewtopic.php?f=23&t=74471
The developers are fans themselves and share a history of friendship/rivalry: the creator of Street Fighter and King of Fighters is the same http://www.1up.com/features/the-man-who-created-street-fighter
Staff went back and forth between both companies (Capcom and SNK), which led to ingame jokes and characters with double meanings, which also led to heated rivalry in the arcades and amongst fans, so why wouldn’t they want to go for round 3 in the HD era. Well now i think we need to ask Capcom that…