So ARM based this on a rumour?

2x Denver2 cores are nVidia chips.

Its got a weaker CPU than the PS4 or XB1, does it matter by how much?

Remember the days when people were stating NX is more powerful than ps4?

seems weak but at the same time CPU doesn't matter a lot now, and PS4 has an AMD, as much as I find their GPU good, can't say the same about AMD CPUs... I do not know Nvidia's record on CPU though, just your AMD quad-core CPU won't probably do as good as an Intel dual-core CPU.
Yet again, it's not so important now, so putting a less costy CPU in the machine makes sense

Nope, it was recently translated betterly again on Reddit and he made no mention of the cores being used, 4G is on the developer kit and the 1080p was his speculation based off the docked video output, and this is now removed by ARM and they stated it's taken down to avoid further confusion.

It would have a weaker CPU than the PS4 but not by a lot if it used a quad core combination of A57s, the CPU wouldn't be a serious issue or bottleneck to developers. But check post update, A72's are back on the table.

IPC (instructions pr clock) are in the same neighborhood performance wise (supposedly).

With half the cores, and half the clock speeds, your looking at something like 1/4th the CPU power.

Maybe its more than that? closer to half the performance of the PS4/XB1 in terms of CPU.

Its still weak though.

ARM's president previously went on record that mobile chips as powerful as PS4/X1 would hit the market in 2017. Did we take that seriously?

Meanwhile - this is probably some errant post by a social media manager. The link it doesn't go back to nVidia, Nintendo, IDC, or other professional source which is likely why it is not confirmed accurate and was removed.

If ARM is talking about their CPU's rather than other companies GPU's then that is pretty easy to achieve. Their Mali gpu chips are not competitive in performance and for lower end devices so I'm sure he didn't mean that.