yeah, this has been covered.
remember, VF5 was coming out in the summer BEFORE the online play was added. suddenly it was october.
i played it in japan in april. it was already locked at 60 FPS on the 360. it would not have taken much work to get it shippable as-is.
suddenly for some MAGICAL REASON sega decided to add online play, something AM2 told me TO MY FACE that they were not going to be doing because it would ruin the gameplay experience. which is widely and well documented as the position of the developers of the series until extremely recently.
i think the poor sales of PS3 VF5 are not 100% attributable to the expense of the PS3 (though that's clearly a major factor.) i think it also relates to how fucking AWESOME the arcade experience of VF5 is. from the IC cards containing your character (with intro/outro/stats) and the VF.net stuff, why would you want to play a home version?
whether or not it makes sense to you that AM2 would be spending their effort and innovation on the arcade version of a game (since it can't be marketed in the US) the pure fact of the matter is that this is true, and they have been doing so. the VF5 arcade experience is hot.
and with that said, online play is clearly for the US/euro audience.
looks like GR's video embeds don't work here, so i'll just link it:
VF5 arcade tour (club sega akihabara)
http://www.gamesradar.com/us/xbox360/game/movies/index.jsp?releaseId=2006122111543685040