I'm going to indulge some completely uneducated guesswork here as hypothesis...
The model til now has generally been that VIP get some advantages over Premium including "free" access to content other than expansions, which generally have been major content releases.
The letter mentions adding value to VIP in addition to mini expansions.
A reasonable conjecture may be that this represents a move to make VIP pay to a much greater extent for the hitherto "free" content they have enjoyed in return for their VIP payments, compensated by some other material incentive.
If so, the compensation would need to be substantial. I can't see VIP being happy. I can't see Premium being happy either.
Didn't the recent due diligence papers show that ddo players already pay a larger contribution than other games into SSGs purse?
In that context, as a consumer, the prospect of this new model doesn't exactly thrill!