"Skype: patched and recompiled to do other stuff" is a better title. Decompiling a proprietary product, changing a few lines of code, and then releasing that code doesn't make it "open source", it makes it stolen code (semantics of "piracy is not theft" aside, it's still not his code to be releasing in it's entirety.).
If you want to stay within the law my understanding is that you need to distribute patches against decompiled Skype rather than decompiled Skype with patches applied, otherwise you're distributing a derivative work. This may still be a legal grey area though. IANAL, you ANAL, we all ANAL and that.
I agree. A lot of the points in this review are simply irrelevant. They're talking about support for HDMI and other features not being available in default Debian distributions, the abililty to render Quake 3 (seriously), and other ridiculous comments.
If you're a hacker/tinkerer/kid learning, the default distribution isn't likely all you'll be using anyway. And if you're buying the Raspberry Pi to try to get a cheap gaming system, you've completely missed the point.
There are so many other problems with email that could be addressed by a new protocol, eg: spam, security.
There are measures to address these issues more broadly with SMTP, but they are not widely adopted, something that could be standardized in a new protocol, ie: encryption by default, message signing to prevent spoofing, encrypted transmission, etc.