She is but my sense from various web articles is that she's acquired richer tastes as well. If you're income/wealth jumps by a factor of 100x you can be set for life. But if your spending/lifestyle costs jumps by a factor of 100x too, then your ramp shortens and you need to stay a working stiff (admittedly at the executive level) just to keep your lifestyle going. But agreed that even despite this effect, it's probably not the Yahoo pay (bump) that motives her, but the jump to CEO and losing the feeling of perhaps hitting a ceiling inside Google. The competition inside Yahoo is likely not as tough as inside Google too, and there's a great opportunity to move the needle. And even if she tanks as CEO or hates it, she still can't really "lose" because she should still have plenty of FU money. So, arguably a heads-I-win / tails-I-dont-lose opportunity.

I don't think money motivates her exactly, but being paid less than the next CEO guy would demotivate her (yes, it comes to the same thing and no, her needing less won't force her to pay more taxes). Pecking order in the peer group matters to most people. That said, I think as a group CEOs are overpaid wrt to the value they bring to shareholders, but boards are made of CEOs, which explains why the Gini keeps rising.

I think she's only worth $33MM right now, so getting another $100,000,000 in the next five years could still be motivating :)

IIRC, this sort of comparision is what started all this CEO salary inflation back in the late 70's/early 80's. The CEO's of billion dollar companies were being paid less than baseball players and cried foul.