Maybe, but an preliminary injunction is not a ruling of fact. There seems to be some disagreement on the Supreme Court over whether an substantial issue of invalidity is still grounds for denying a preliminary injunction, because even a substantial challenge does not mean the plaintiff won't win. These judges are not ruling on the validity of the patent, but merely whether undue harm results lacking clear evidence of invalidity.
I always assumed there was more to it than Apple patenting a rectangle, but a judge holding them up side-by-side for comparison would appear to indicate otherwise.
Also don't read too much into the lack of challenge of other manufacturers. Samsung is rapidly gaining on Apple's smartphone share, and you don't sue all potential infringers at once. You try to get a favorable judgement and use to leverage license agreements with other potential infringers. I think Apple targeted Samsung because of additional claims with the icons and UI - i.e. the most likely target to get a favorable judgement on.
Looks like the ruling in Australia has to do with "touchscreen technology and other features". Samsung could very well be infringing on the architecture Apple patented (but otherwise I doubt touchscreen interface is patentable, Apple wasn't even the first). As a key supplier, Samsung could very well have stolen or piggy-backed some underlying Apple engineering or software to power various functionality.
In the Netherlands, they've apparently modified banned phones and are set to release them. According to Reuters, the patent at issue was a method of scrolling through photos!
Apple Gains Patent Ground On Samsung As Sides Square Up On U.S. Soil | paidContent
"
Patent blogger Florian Mueller
points out that the patent in question that was exercised in the case is one registered to the late Steve Jobs (among others) and concerns “heuristic touchscreen” technology.
The generality of the patent, he speculates, could be applied to a number of other tablets, not just Samsung’s, and the fact that the Australian court has chosen to support it means that Apple may now have the legal ammunition to go after other competitors looking to launch products in Australia."
Anyway, it seems like all the hub-bug over Samsung getting taken to the woodshed for "copying the look" has been a little off-target.