but why does the government want to step on your opinion?

I don't think they're trying to make every person justify their internet opinion or face penalty, I think they're just trying to make a framework whereby if a person consistantly raves about the quality of Universal's films, and is later found to have an undisclosed arrangement with Universal, that person can be punished.

Penalties can be easily avoided by either not having a conflict of interest, or by openly disclosing your conflict of interest (which responsible bloggers already do). There's no need to alter your opinion or keep quiet about it, even if you're a paid employee of Universal or some marketing agency.

The only bit I don't like is the bit where it states 'if you have a general dislike of...'.

That seems to be saying you're not allowed to be biased. Which is stupid.
This should only apply where people have a conflict of interest, as in they have some fiscal (or material) gain from putting out their opinion.

"Journalists who work for established news organizations are often not allowed to accept payments or gifts from marketers. Such organizations often have stringent policies in order to reduce conflicts of interest and ensure and maintain credibility with their respective audiences."

Anyone think this is actually true for the mostly-amateur gaming press?

Nope. We don't but a lot of the other smaller press sites, and probably larger ones too, will do anything to get hits so they will market a game and receive gifts for giving good word for games even if the game is horrible.  In turn the marketing will increase hits and gain them a fanbase plus gain a small cash flow. I've seen many small press sites come and go because of this.

Off-Topic: Nice avatar Keith!! Kind of goes with mine in a way.

How many small bloggers will not be afraid to write bad review about game x if they know they can be prosecuted for it and in best case they will have to do few hours of paperwork.

It will be much safer to never criticize anyone too much.

I sense a lawsuit coming on the grounds of freedom of speech violations. Actually I hope the lawsuits come fast and heavy. BTW who actually goes to blogs to get news? most bloggers are political hacks looking to push readerships and agendas.

You're blowing this out of proportion. They're not going to be flinging lawsuits around challenging every petty remark on the internet, as that would be such a ridiculous waste of time as to make the law unenforcable.

Nobody is going to prosecute unless:

1. There is a provable conflict of interest and

2. The blogger fails to openly disclose it.

There no violation of freedom of speech, because people are still free to say whatever they like. But if they speak about a subject which involves their livelihood, they have to add a little bit of information which they might otherwise prefer to be left unsaid.

Is it a violation of freedom of speech when political ads are forced to disclose who paid for the ad?

Yes, it is a violation of freedom of speech. I don't believe anybody has the right to tell you that you must tell people who is paying for what you are saying. It is the consumers responsibility to research the data. However, if you are in the public spotlight, you should have the scruples to disclose who is paying you to say what.  

Of course there will be lawsuits it's only a matter of finding company which will be asshole enough to try to hunt all negative opinions about it's product (activision comes as first possible candidate to the mind)

And for most cases it will be same autocensorship as ESRB introduced to games - where authors are afraid of putting risky content in fear of receiving AO.