Yes, you can switch to windowed mode and multi-task sensu-stricto.

BUT, there is no swap at the moment, so you might get the backgrounded process killed due to OOM management, unless you fiddle "nice"ly. I am part guessing here but I do not see how this would not be the case.

The "user shouldn't care" comment is about plain vanilla phone users. Indeed, they shouldn't care in principle, if the phone provides what they are looking for. By and large it does (lamentable lack of apps aside). BUT there are some notable shortfalls: for eg. you can only capture a GPS trail by keeping the screen active, otherwise the app goes to suspend. Canonical devs are WELL aware of criticisms of this and the issue is discussed.

Thing is - and I believe people generally underestimate this point - the official dev team is pretty small and they struggle with the balance of delivering new features and bug fixing. At present, convergence gets most love and there are some VERY frustrating issues on the back-burner (Meizu (and BQ?) battery levels, anyone?).

This point is crucial if one's expectations of UT are to be realistic. What I don't know, is if and how Canonical are going to get that point across to prospective purchasers in order to be fair to them. The hype behind the state of readiness somewhat exceeds reality. Not by much but IMO enough to piss some (many?) buyers off. At least, that is what I saw in the previous round of (first) releases.

Go here and read if you will, the general tenor of exchanges between devs and between devs and power-users and the topics covered. Keep in mind that it is not a support forum.

One other thing: the inputs on the ubuntu forums about Ubuntu Touch are rather sparse and lacking. The forums seem not to have captured much interest of phone users.