Flawed stats that still try to make Apple look better
"Not quite keeping up with the iPhone 4S" is a completely biased comparison - Apple only have one phone per generation, where Samsung have loads.
The only useful stats are either comparing by platform (Android is way ahead of IPhone), or by company (where Apple are third behind Samsung and Nokia). Comparing by individual phone models is a useless stat, as it means that it's biased towards a company that has fewer models. *Worse*, it depends on how the models are labelled. Samsung and Nokia typically give different model names for small variations, whilst Apple don't. Why should a model have a different name just because it has a faster CPU, but not if it has more storage space, for example?
Any metric that can be changed simply by conducting a relabelling exercise is useless. If one ice cream company sells 100 cones, whilst another one sells 90 cones without flake, and 90 cones with flake, only a spin artist would suggest that the former is doing better!
I also note that this article doesn't say the IPhone 4S is selling better, it merely handpicks the statistic of selling X in so many days, which Apple always do better on (because the fanatics rush out and buy it immediately).
It's interesting to look at the history of Apple media coverage:
1. IPhone is number one (conveniently forget about Symbian, number one until 2011).
2. IPhone is outselling Android (conveniently forget about Symbian).
3. Okay, Android is outselling IPhone, but Apple are still the number one company (conveniently forget about Nokia)!
4. Okay, Samsung is way outselling Apple - but IPhone 4S is still selling more than Samsung Galaxy S3!!!
What will happen when the S3 is outselling the 4S (which is already happening in some markets, e.g., the top model in the UK for a year has been the S2 and now the S3)? My guess is the media will then switch to "Iphone 5 outsells Galaxy Note 2" - already the media are making the comparisons, since these two phones are expected to be released around similar times.
"making it the most popular smartphone series in the world"
Talking about a "series" is even more meaningless than models. Why do all of Apple's phones count as a single "series", but not all of Samsung's Android phones? The fact is that Samsung have been selling more smartphones than Apple (and that's before we get to the point that "smartphone" is ill-defined - why is the original Iphone, which couldn't even do apps, a smartphone, whilst many phones get labelled "feature" phones? This just means that 100% of Apple phones get compared to only a minority of Samsung's and Nokia's). It's kind of sad that stories about the immense success of Android and Samsung have to be blighted by this attempt to hand-pick stats to go on about Apple all the time, and make them look better (and I'm not just talking about this story - The Reg are one of the better places for fairly covering all the technology companies, the problem is more with the rest of the mainstream media).