Probably a solid 7.5 right now with a chance of going up to an 8.5 or down to a 6.5 depending on if they make good on the 'new stuff to do all the time' mantra.
Its biggest cons for me are: Some very clunky UI (could we just turn tooltips off, please?); lack of real audio setting; and a storyline that is good in theory, but disjointed and weak in practice.
However all of that can be overlooked if we get fun, long lasting end game content.