So we still don't know when the Eberron Player's Guide comes out, which actually has the full Artificer class write-up in it.
I just have a slight issue with Arcane Power than, since it comes out before the EbPG so it likely won't cover all arcane classes. Yes I know it's a problem with there going to be 6 arcane classes with Wizard and Warlock from PHB1, Swordmage from FRPG, Bard and Sorcerer from PHB2 and Artificer from EbPG.
Yes, I know the Wizard really does need a lot of help with new material, since it feels a little lacking in some areas with the PHB. And with the much wanted new warlock pacts, there's enough powers to make it as big as the PHB warlock entry.
Really it would look better if they tried Divine Power first, since by then we'd have the Cleric and Paladin from PHB1, and the highly speculated Inquisitor and Theurge from PHB2 and have the divine power source "complete" with that book.
With Martial Power it's good that there's no new classes, since I can't see how they'd try to come up with more martial classes. That power source is pretty complete, though I'd like to see some newer options like a ranged attack path for fighters (which could help with my homebrew ideas for a rifleman as a fighter).
I still don't like that I'll have to likely wait till 2010 till we have the monk or psionic classes (with the psion likely existing as a playtest class in late 2009). Though maybe by then they'll have a book on Aberrant creatures much like Lords of Madness, to go with psionics.
Then again for late 2009, I wonder if they'll bother with a Primal Power book, since it seems that with PHB 2, the 4 proposed primal classes will likely cover all of the Primal power source (barbarian, druid, shaman, W?/witch?/wu jen?) that there needs to be.