Castlevania Producer leaks info
 

Castlevania Creator Hints At New Title
Whatever it is, we'll see it at E3.

January 16, 2003 - Castlevania producer Koji Igarashi has another project in development alongside the Game Boy Advance title Castlevania: Aria of Sorrow, he announced today at Konami's gamers' day event. No title was given -- all he was willing to say is that the game is not for a hand-held system, and that it will debut at this year's E3 show.
You may commence to envision a next-generation Castlevania game at your leisure, but we will keep an open mind until more concrete details arise. Look forward to it.

Source

I'm pretty sure it probably is a Castlevania game, since not only there's that hint at a new title, but also the thing in PSM where the guy said that there WILL be a new Castlevania title in 2003 for a home console (as in not handheld)... least I think he said that...

Haha, wouldn't that be funny if it was on Gamecube.. and it hooked up to AoS... well.. it wouldn't be funny. But.... eh. :p