What moves is sakurai taking from PM? I haven't noticed any.
There have been more than a couple examples, unfortunately the only one that comes to mind right now is DK's dash attack (yeah, it's from DK Country, but for whatever reason it wasn't in any of the previous Smash games).
What? I'm always blunt like that.
EVERYONE should know of the bad hacks in brawl. Some include-
-Infinite Giga Bowser online
-Infinite Wario Man online
-Custom stages online (giant boxes where you can't die)
None of those are mods.
Infinite Giga Bowser - A cleverly edited Youtube video done for an April Fool's joke. Not real.
Infinite Wario Man - Looks like the poster is claiming they used a hacking tool called 'Ocarina,' which is a real thing. I wasn't able to determine whether this actually made it online or if the video was edited.
Custom cage stages - An exploit in the custom stage builder. No hack required, and it's very easy to do yourself.
You're talking about disruptions of service; we're talking about modifying a game to make an altered product. There is a huge difference, and it's perfectly fine to accept one without the other - but please, understand that P:M is a mod, and does not belong in the same category as the things you've listed.
I understand your concern though, which is why I'd like to remind you that P:M players, while using the same online service as Brawl, couldn't compete with or interfere with Brawl players (and still can't, even if you're using the alternate online service today... which is available because of hacks, by the way).
If your reasoning for hating P:M is because you fear for the fidelity of Nintendo's online service, I ask that you reevaluate your reasoning. P:M players are not cheaters (well, not most of us anyway).
Mods and those cheats sprout from the same methods. You can install the Hombrew channel on Wii the same way you install project M. I'm saying they go hand in hand. If you have a way like what you do to install project M, you WILL have people abuse it. Isn't it better to not have it then?
If that's the way you want to think of it, then look at it this way; Mods are the mature version of hacks (and vice versa). Hacks are like the wheat that go into your bread - a necessary ingredient that leads to the creation of something better.
If you really want to ban mods because their ingredients can be used for harm, then I suppose we should also ban fire, water, nuclear energy, sodium and chloride (necessary ingredients for salt, both of which are incredibly dangerous by themselves)... etc.
What it boils down to is this: Mods are not the problem. Hacks aren't even the problem.
People are the problem.