Re: I don't fully understand...
'Your argument (possibly made more in hope than expectation) is "Not illegal. Because internet."'
Can we please distinguish between the internet as a whole and the WWW? That's an important distinction to make because hyperlinks are how the web works; no hyperlinks, no web. Every page on The Register has loads of them. So can we get rid of the notion that hyperlinks in themselves are illegal or a breach of copyright?
We then have to consider some of the areas of complaint. One is the row about deep linking. One site publishes content. Another has a link to that content. First site complains that its content is being "stolen". As above, hyperlinks are how the web works. If you don't want people to link to it, don't publish it on the web. Possibly the context in which the deep-linked material is presented is intended to deceive the viewer into thinking that it was the second site's work. In that situation there may be a case to answer but it's a case about the deceptive presentation, not the link itself.
The other is material uploaded and made in breach of copyright. That's the offence. A link to it is, in itself, no more than a statement of fact. To go beyond that you have to look at the circumstances in which the statement is made.
Take an example: You tell me that you're looking for a good picture of a sunset. I find a really cracking example on the web and email you a link. It turns out that the picture was actually a third party's picture, uploaded in breach of copyright but with no indication that that was the case. All I've done is make, in all innocence, a factual statement as to where you can find what you were looking for.
If someone is publishing a list of links to such material in a context where there's a clear implication, if not an outright statement that the material is hooky then secondary liability comes into play but it's not the links themselves that are the problem, it's the context which forms an incitement to commit further breaches of copyright that should give rise to secondary liability. What's more it's not the communication's being in the form of a list of hyperlinks that gives rise to the liability, the same liability arises from telling someone that there are stolen phones for sale in a particular pub.