The who is creators, the value is "infinity or zero."
Everyone on here seems to be doing the money maths about land, which has me head-scratching. Think about the discount you get from the regular Premium plan:
Basic account: 7 USD, you get a 1024
Premium account: 8.25 USD, you get a 1024
No discount, no value. The added value of the Premium plan is not a discount tier. It's that it gives you a set of software features that you simply can't have with a basic account. Is it worth the extra 1.25/month for 28 extra groups? Certainly doesn't cost LL that. The offer isn't a "deal" on anything the lower account type has--it's additional features that the lower account hasn't got.
Then, consider whether Premium Plus is doing anything so different:
Basic Account: 13 USD, 2048 land tier
Premium+ Account: 20.75 USD, 2048 land tier
No discount, no value. Same arrangement--they give you the highest amount of land tier that fits within what you've paid. And then double your groups, increase your message cap, etc...and then free textures, sounds, animations with more to come (yes, they said mesh is coming). Again, it's the "stuff from lower tiers that you've more-than-paid-for," plus features you don't get at those tiers.
Premium isn't going away. And I think many people should stay with it, myself included. But I think a lot of people are disappointed that P+ isn't some sort of "Premium, but a cheaper deal in the long run" and is, instead, another set of costlier feature offerings at a higher price, and I don't know why we would suspect that LL would grant us all double land while cutting their bottom line on tier fees in some way.
Creators, though? Fixed business cost. That's a huge value offer to a certain set of the SL population.