There's some major cognitive dissonance going on here, seeing Twitter hashtags on Google Plus.
It really hits you over the head with how limiting (and, frankly, silly) Twitter is. I think in a few years people will look back at Twitter and feel like they were, well, duped in a way -- millions of grown men and women, adults, typing in obscure abbreviations and making up messy syntaxes just to fit a semi-arbitrary character limit; large, important companies falling over themselves to play the game and Build Their Brands around these tiny messages; opportunists positioning themselves as gurus of this Sophisticated New Communication Platform™.
It feels like the Twitter founders are sitting in a room somewhere, laughing at how they've gotten millions of otherwise-sane people to jump through these absurd hoops -- and that, deep down, even the most guru-y of the Social Media Gurus ask themselves from time to time, "Seriously, I'm doing this?"
Anyway, it feels like G+ should have something much more sophisticated and user-friendly.