"If you think about it, if we tried to build all of the above on top of npm, it would be npm in name only. Even if Meteor packages were in npm, you wouldn't use the npm tool to find or install packages (you'd use a wrapper that implemented the 'release snapshots', 'curation', 'repeatability' considerations), nor could you drop them directly into existing npm applications (per 'client vs server' and 'asset bundling')."
That's a good find but I'm not suggesting they wrap npm, but that they fork it. I don't think this comment explains why they couldn't fork their spangly new system from a robust existing one.
"If you think about it, if we tried to build all of the above on top of npm, it would be npm in name only. Even if Meteor packages were in npm, you wouldn't use the npm tool to find or install packages (you'd use a wrapper that implemented the 'release snapshots', 'curation', 'repeatability' considerations), nor could you drop them directly into existing npm applications (per 'client vs server' and 'asset bundling')."