Uh... as I understand that, it only applies to 'qualified' dividends, though that's most dividends that have been paid out in the US in the last 8 years. It's also income-sensitive; I believe qualified dividends have 0% tax for the bottom two tax brackets (e.g. the same as long-term capital gains taxes). Regardless, the rate is set to go up in January to income tax levels if the law isn't changed.
As for the investment tax, while I agree with you that it's not a great idea expanding the base for Medicare taxes, it does only apply to incomes over 200k/250k. Effectively for dividends, it's raising the 2011 rate from 39.6% to ~43% (I'm not sure if the extra 0.9% is included or just the 2.9% inclusion).
Wait a second, I though long-term capital gains would revert to 20%, not the marginal income tax rate?Separately, capital gains taxes could possibly go anywhere. Obama's proposal to set capital gains rates at 20% is a mess because this Congress has been using blunt "pay-as-you-go" rules to interpret all tax cuts as revenue cuts. This means it's procedurally impossible for them to stick to Obama's proposal. In April the Senate Budget Committee advanced a bill setting the 2011 capital gains rate at 39%. Basically, it's a mess. Hopefully Tuesday will clear it up.