The i7's available for the T480 are quite different to the ones in the T470 so perhaps they don't need to.

The i7-8550U benches about equal to my i7-7700HQ in real world use at half the TDP (so better battery life) though I'd be curious to see how it holds up under load for my workloads so perhaps they won't bother with a T480P, I've not seen any rumours so far.

I have a P50 running Arch Linux. I upgraded from a W520 and thought the keyboard would be a problem, but the keyboard is actually nice once you get used to it. Everything else works except for the fingerprint sensor and there's a project for that (https://github.com/nmikhailov/Validity90)

Yes and no, it is much thicker than the regular T470's but it's still not thick by any measure I'd care about.

My criteria for too thick/heavy is "can I use it on my knee for a few hours without it feeling like someone parked a deathstar on my legs?" in that realm the T470P is just fine.

Aesthetically they are marmite though especially when put next to my GF's Asus Zenbook (One looks like it came from an advanced society, the other like it's used by the engineers of that advanced society).

The really strange one for me was that the T470P lacks a Thunderbolt 3 port despite the 470's having it.

Not a big issue for me because I drive a 4K display with DP just fine, I'd also have liked to have not gotten the 940MX, nothing wrong with it I just don't use it, the onboard intel graphics are absolutely fine for 99.9% of what I do.

Honestly I love the thing, it's been the least hassle, nicest laptop I've had since (ironically) my last Thinkpad around ~2003.