First thing's first.... if you didn't really play enough FFXI to any serious degree, feel free to NOT make comments about things like the story or even go so far as to say it sucks. You don't know.
About the numbered thing... well, I sort of agree, but the ship has sailed... long ago. Obviously they are going to use the traditional series numbers for the online games.
Don't say it's not a "real" FF. How do you define a "real" FF game? It's got Cid, Chocobos, deep storyline (honestly deeper than any of the offline FFs). It's a Final Fantasy game if SE put Final Fantasy on the logo.
Now on to the real topic. All though I quit FFXI long ago due to SE's beyond terrible customer service and the impacts thereof on the game... the game was awesome and had a flavor that is irreplaceable. My wife and I both have an immense amount of nostalgia for it. I'm glad to see it continuing and the press conference makes me feel even better. It seems that SE is going to try to learn from their mistakes. Depending on how much they learn from their mistakes this game could be incredible.
For those thinking it will flop... you are simply wrong. It's going to likely attract the vast majority of FFXI players old and new (especially with them sending the death knell for FFXI in the press conference). If they fix most of the problems of FFXI then they will probably keep a large base.
Keep in mind FFXI has a fairly consistent base of 500,000 7 years in. While you might think this is a failure compared to WoW's 11 million this just isn't true. Just because something isn't #1 in sales doesn't make it a failure. As long as it is consistently sustainable and doesn't have a trend downward (losing players constantly) then it's a success. The thought that FFXIV won't achieve this after fixing the flaws of FFXI (which has achieved relative success) is just illogical.
Hopefully they make it approachable enough that some of you give it a try. While I still have my reservations about it (MMO+console = ugh, cross-region servers = racism), I think it will probably be pretty decent and I'm looking very forward to it.