Agreed. I'm currently working on a startup that's focusing pretty heavily on that (
http://www.tabrat.com/), and let me tell you, even if somebody were to get it 'exactly right', it would still be quite the uphill battle to get it adopted. That's assuming it's a legitimate re-imagining that deviates from the current system of course, and not some C++ style superset. Nothing wrong with teaching an old dog new tricks (in fact it's what we're planning to do in the meantime), but it wouldn't really be anything new, because that is exactly how music notation evolved to be how it is today (excluding tablature for fretted instruments, which should be considered a good, albeit limited, innovation in it's own right).
The people that use notation the most, and take it the most seriously, are usually the ones that have invested a ton of time learning to sight read and knowing how to properly express their ideas in it; hence they are almost certainly going to be hesitant about switching to a new format. We musicians tend to be a conservative bunch; after our first few years playing/experimenting, we pretty much solidify what we like and hardly ever deviate from it afterwards.
I (a guitarist) for example, only really play 2 brands of strings, I have already made vast generalizations in my head about what amp/guitar/pedal brands I like and don't like (as opposed to judging on a product-by-product basis like I would for most other things), and I don't see that changing soon. Likewise, once you develop your notation style, it would probably be hard to really think of trying something new when you've just come up with a cool riff and get caught up in the heat of the moment trying to build on it.
Although I can't wait to see the day the next evolution in songwriting starts getting widely adopted, I can't say that what we have now is really that bad. Traditional staff sheet music does makes it easy to 'visualize' what a piece sounds like, and that's a feat that even well notated tablature can sometimes struggle to convey.
As for my startup? We just want musicians to be able to precisely jot down something like this on a moment's whim (fx and all):
http://www.youtube.com/watch?v=YU52hGo3nNc