Samsung's User Agent Profile (UAProf) has proven to be very helpful lately, confirming the Galaxy Note III and now, a new line of tablets in the form of the SM-P900 series. More specifically, models P900, P901 and P905, where are models 2, 3 and 4? We don't know, they might be reserved for future variations on any of those tablets.
All of them are running Android 4.2 Jelly Bean, most likely 4.2.2 considering Samsung's latest releases, and an ARM 11 processor although we don't know which. Each model has a different connectivity, with the P900 having both Wi-Fi and 3G, the P901 is a WiFi only tablet and the P905 has Wi-Fi, 3G and 4G LTE.
The most notable characteristic that stands out of these UAProfs is the resolution, they all have a 2560 x 1600 display, just like the Nexus 10 has, which is also made by Samsung. We don't have any more data on these devices, but the rumors point out as the Galaxy Tab 3 Plus family which should be announced later this year, probably during IFA in September.
Since the models begin with a P instead of an N, we take it that they're not part of the Note line so won't be enjoying any of the S-Pen functionality, which Samsung keeps exclusively to its Note devices.
The resolution alone makes this line of tablets a product to be followed closely, if Samsung is making them, we can hope to see this kind of high-resolution tablets flood the market in no time. even if these turn out to be flops, we can expect competition from the likes of ASUS, Acer and Sony (the only ones currently manufacturing tablets) follow closely to the market with high-resolution tablets so they won't be left behind. The last thing the market needs is Samsung extending its reach and opening the gap with the other manufacturers even more.
I guess we can all safely assume that with this news and the fact that ASUS is the one making the new Nexus 7, Samsung will be the one in charge of producing the evolution of the Nexus 10 for Google.