Voted 7.

I love BI, but since its being sold as an expansion we should distinguish between that what should have been there already or should have been patched (for free), and that what is actually worth paying for again.

In the latter category are, IMHO, only the big new features such as night battles and the horde feature. I think above all the horde feature, because of the new type of campaign it creates through its cascading effects, is what gives BI the right to be called on expansion and not just an elaborate patch.

All other improvements/changes/etc, such as better AI, 'new' map, 'new' units, new vices (overdone I think), etc, should either have been in the original game or been patched, could have been modded (/should have been moddable), or are just not that interesting. Also, some of the new features could have been implemented better (development of your generals sucks now, hordes are irritatingly difficult to kill off, etc).

So, given all that, a 7 is still not a bad score. And given that RTW 1.2 is as it is, BI is definitely some of my best money spent on any game (not just referring to expansions). Of course, on second place after VI.