Edit: Agreed with @caipre's reply that the quote isn't as bad as it sounds totally out of context (in hindsight I should have included more of the context in my reply too), and was probably meant tongue-in-cheek. However, I think considering the (perceived? real?) animosity between these two projects, his choice of wording could have been better.
The quote in context isn't nearly as damning as GP made it out to be. It seems to me that Hammond was answering tongue-in-cheek and only meant to emphasize that his focus was on Node.js alone:
One more thing: Developers using IO instead of Node are,
well, not invited.
“IO.js, what’s that?” asked Joyent CEO Scott Hammond in
response to my query about whether projects based on the
fork would be able to enter. “This is a Node.js project
for Node.js innovations.”
I'm not sure I can take the criticism seriously after seeing the source.