I get the feeling that these [url=http://www.nofrag.com/2010/jan/08/33345/]rumor is utterly ridiculous and baseless. After all, who would want to take on Planetside as the best MMOFPS out there? Oh, wait.
This after the rumor that there could be a first person Infinity Ward MMO, and that Blizzard and IW are owned by the same evil empire, might this be a collaboration of some sort?
Conspiracy theorists, begin.

Another fantasy RPG-ish MMO made by Blizzard will just cannibalize WoW's userbase, therefore it kinda makes sense for Bliz to make a distinctly different MMO.

You have a point there.
But Blizz don't have any experience with FPS games, do they? Such thing can be a step into the wrong direction.

Actually, you can already play WoW in 1st-person view, if you want... well...

I couldn't care less, to be honest. But have been hoping for a while that id and Bethesda would pool their resources into an open world FPS/RPG hybrid.

Isn't that Hexen?

They didn't have any experience with MMOs before WoW either.. :P

Fallout 3?

With better combat, yes. Or Rage with more RPG elements. Either works.

What about their shelved work on Starcraft Ghost? There's some experience right there, even though that was 3rd-person. It seems that Blizzard really want to make some leap into that shooter action somehow. If they did, wouldn't it be cool if it became bigger than Modern Warfare?

I wouldn't mind shooting a few million Warlocks...

It would be fairly illogical to have the new game just be a copy of WoW with only a different setting and different abilities especially given that WoW can go on forever with a few engine/graphical updates here and there. Blizzard has the MMO genre covered with WoW, the RTS genre covered with SC2, and the ARPG genre covered with Diablo 3. The only other major (and still active, i.e., not counting space sims and adventure games) genre is the FPS. From the rumor description it sounds like it will be similar to Global Agenda (which would doubtlessly tank in the wake of a Blizzard created alternative). To maximize profit you want to give consumers something unique that they'll shell out another $15/mo for as opposed to something mutually exclusive to WoW.
So, yeah, probably something like Global Agenda or Borderlands with better class/talent/item/multiplayer implementation.

Blizzard just aquired the full rights to all 3 Redneck Rampages, they own it all 100%...
Redneck Rampage MMO --- OH YEAH!

Come to Texas, I'll show you a Redneck Rampage MMO...

In Redneck Rampage they're all ultra-violent, mindless clones of one another, who all embody the worst in redneck stereotypes.
Oh...