When the DDO loading screen first announced that Module 5 would have an "improved" metamagic system, nobody thought the costs for applying metamagic to spells would change. The assumption was that the UI to choose when to use metamagic would be revamped, because that is the most bothersome part of metamagic in DDO. After all, there have been many complaints about the UI and hardly any about the point costs.
The problem with the current system is that it is too slow and difficult to toggle metamagics. To activate them you must hit an icon and then stand still waiting for a progress bar to complete. Yes, the progress bar is quite fast, but it still takes nonzero time. All players would enjoy a fix like making the progress instantaneous, and/or allowing you to drag metamagic feats onto specific spell icons ahead of time ("metamagic spell sets").
However, as it turns out, the new system for metamagic pricing will exacerbate the UI problems. That's because the metamagic costs for high-level spells will be relatively lower than for low-level spells, whereas right now they're the same. A player who wants to achieve a certain goal with his spellcasting will need to switch metamagics on and off more frequently if he is using a mix of low and high level spells.
Scenario 1
A sorcerer is dealing damage to individual monsters with the Disintegrate and Scorching Ray spells. There are a lot of monsters, so you want the most damage-per-spellpoint efficiency. You have Empower Spell and Improved Empower III.
Current system: For most damage-per-spellpoint, you do not use any metamagics.
New system: Disintegrate will do more damage-per-spellpoint with Empower, but Scorching Ray will do less. Thus you'll be trying to switch Empower on and off between each shot.
Scenario 2
A cleric is going into melee throughout a quest, which means casting the Divine Favor and Divine Power spells. Your goal is duration-per-spellpoint, or minimizing the sp it takes to keep those buffs on throughout the battles.
Current system: You use Extend Spell on both DF and DP, as it gives both spells 2x length for 1.5x cost.
New system: You use Extend Spell on DP but not on DF, because DP gets 2x length for 1.6x cost, while it would give DF 2x length for 2.5x cost. Thus each time you're going into battle and casting those spells, you need to turn a feat on or off.
As you can clearly see, the new system will reward spellcasters who can switch metamagic on and off more frequently. And to take advantage of the benefits, we'll have to suffer through the awkward progress-bar activation more frequently.