Since there will likely be two models I'll include both in each option.  I think they'll go with $399 for a 500gb system and $499 for a 1tb system.  I don't think they can go any lower than 500gb because that's the high end PS3 model now and obviously they won't go down in storage with all this online focus.  Games will be bigger and with trying out every game they won't want to skimp on the space.

EDIT:  Hey guys just to provide some cost info you can get a 1tb for $70 on Amazon and I'm sure Sony will get them a lot cheaper than that.  Here's hoping they go non-proprietary.  Also for those of you suggesting they go SSD I really don't think that's happening.  They've already said it will be an HDD at the conference and those are way too much I mean I found a 128gb one for $100 but wouldn't it be confusing to the average consumer if there was more cost for less space (I know they eliminate loading times and offer other advantages but just in general).  I suppose a store employee could help but I wouldn't trust them to be unbiased given what I've heard and experienced.

Hopefully the low end will be 32 GB flash memory. I want the console to be as cheap as possible. I can get an HDD cheaper than Sony can offer with the console.

I'd say 32 GB and 500 GB.

It's pure speculation, but I'm pretty sure we'll be seeing 500 GB and only one model at launch. Later on there will be PS4 packs with 1 TB or even more, but I really hope that I can use standard Hard Drives again. That way I could just use my 1 TB Disk that I'm using inside my PS3 right now.

It's a bit of off-topic, but I don't think there will be two models at launch. As we saw with the Wii U, it only leads to customersbeing irritaded and early adopters don't want a dumbed down version anyways. Anyone who gives a crap about price won't buy the system at launch anyway. So a cheap model wouldn't make any sense. Let's be honest, does the price really matter? Probably. But not to me, I payed FIVE HUNDRED NINETY-NINE Eurso (That's even more than 599 $!) for the PS3 and would do the same for PS4. But granted, that's just me. :P

It has to have at least 1 TB of space, cosidering 4K

500GB standard. They may add in a SSD option but at $1 a gig, it's still expensive.

Although if they have media cloud support, then that would mean a 120gb variant could be possible but personally I think a 60gb SSD variant is more realistic given the price of SSD. Whether it would be filled up quickly with installations is another matter. At 1-3gb an installation you could get a good amount of saves (saves could be cloud based as well tbh) & installs on it, and with demos being cloud-based it is quite feasible.

I actually agree with you.  If you offer superior hardware and don't charge for online while your competitor does it justifies the cost.  Hell PS3 sold better than 360 in each respective year of their lives despite being $200 more for each model at launch.  However launching against Nextbox and people looking at them both on the shelf at Christmas may be swayed by a $100 cheaper model.  Launch day people and hardcore fans all want the high end model obviously.  I hope they have a 1tb option cause I don't feel like upgrading the HDD tbh.  Maybe when they come out with a slim I will anyway and then I can just transfer but hopefully at least 500gb at launch (PS+ will fill it up over time).

Not really. Making your system have a HDD large enough for 4k files is just saying "HAI GUISE PIRATE 4K, K?"

It's why there's no MKV support on PS3. Sony are going to want you to play 4k from bluray, not via your HDD. 

250 GB and 500 GB. They want to keep the price reasonable and they don't want that to cost them too much so no 1 TB just yet. And I doubt they can go lower that 250 GB with their plans unless they really want to screw the less-informed customers.

I'm going to go out on a limb and say.. 500GB for the premium model.

The problem with Wii U is that the differences are much bigger than just the size of the disc, making the regular Wii U pretty much ridiculous in comparison. If the only difference is the size of the HDD (or the lack of it) it won't create confusion or irritation. Early adopters don't care about the price, but you want to sell consoles after the first 2-3 weeks, don't you? Trust me, a lot of X360s, DSs and 3DSs got sold just because they were cheaper than the competition from Sony. A cheap version is a must if Sony doesn't want to have yet another console struggling like hell from the start. I hope they've learned this from the X360 512 MB and 4 GB versions and their own PS3 12 GB version.