Look at how powerful he was, just as powerful as Yoda.  Could Palpatine sense Yoda was alive in the fight scene after he was knocked over at first, or after he disappeared down the chute? Ever cross your mind that powerful a Jedi or Sith could mask their presense if they really wanted to?  Seems pretty logical to me.

All Palpatine did is play on his emotions to give him the final shove.  Killing Dooku was the second step down the path, the temptation just brought him over, not to mention whatever mind tricks Palpatine had been using on Anakin the whole time they were friends.

Oh sure he's a whiney bastard, but you know what?  There are a hell of a lot of whiney bastards out there in real life, and seeing the ultimate bad guy start out as one, I think, kind of sends a nice subtle message to all the little ungrateful, selfish brats in the world.  It also is just another facet of his lust for power.  It's tragic, but in a way it makes you want to see Obi-Wan spork him over in a big way, and we do.  There's a lesson to be learned here, maybe that's why it annoys so many people.  "You'll get yours, Benny!"  

About the Padme choke scene:  no rationalization is needed, he lost his mind during a psychotic episode and his anger was ruling him.  You don't have to be a Sith to do this, average modern humans do this sort of thing every day.  We just call it Domestic Abuse(tm).

My problem with Anakin's downfall is two-fold.  One, the whole entire relationship between Padme and Anakin has been way too forced throughout the series, and I found the gap of time between episode II and episode III to further compound that.  People may bitch about Anakin being a whiny, emotional brat, but if blind love is his downfall, then his intense attachment to Padme should have been delved into more or at least shown more readily in a simple scene such as Anakin freaking out over Padme tripping or something along those lines.  Secondly, the other major catalyst for Anakin crossing over is him being torn between duty and Jedi code.  In Star Wars lore in general, the Jedi are notorious for keeping people in the dark in order to protect them, but it generally winds up screwing them more than it helps.  Anyhow, Anakin might not have been thinking clearly after knocking off Mace Windu, but he should have had second thoughts about killing all those people in the Jedi Enclave.  Remember how he said that he shouldn't have killed Dooku?  Jedi don't kill their enemies unless forced, Anakin would have been judged for his crimes and at worst, exiled.  The fact that Anakin accepted so readily when he was so strongly attached to the Jedi code, kills a bit of the believability for me.  Granted love overpowered Anakin's better judgement, but here again, the whole attachment thing could have been done better in my mind.

 Going back to the large gap of time between Episode II or Episode III... Who the spork was General Grevious?  I shouldn't have to watch a cartoon series to learn about the background of an important character present in a movie.  Hell they could have at least explained or hinted at what happened to the bastard for him to become some kind of quad-lightsaber-wielding cyborg.  Oh and the one sentence explanation to answer "What happened to all the fighter droids?" was bad, but I'm not going to dwell on it much.  It fulfilled its purpose. And I liked the droid chatter even though the R2-D2 scream was a bit overused. :p

  The whole damn trilogy has been rediculously over the top in terms of special effects and extraneous scenes.  Episode 1's pod race was too heavily focused on to the point where I felt as if it was being pushed as the highlight of the movie which really contributed nothing to the story-line other than Anakin winning his freedom if I remember correctly.  And my god, Padme's hairstyles and outfits...  (The whole of episode 1felt as if Lucas was attempting to sell me a car while continuously telling me how shiny the car is.)   Episode 2 had a horrifically low live cast, (I'll take puppets over CG any day,) but it at least had enough sense to save all the major CG for one epic battle.  Episode 3, on the other hand, made every battle epic, even ones that were totally arbitrary and used as transition scenes.  That really hurt the character development in my mind, and it also disrupted the pacing of the story.  The only good epic battle was the one we were all waiting to see, Anakin vs Obi-wan.  The light-saber choreography also seemed noticably better, but then again, the two characters involved in the fight were both live actors this time.

I actually found it rather believable.  Granted, it could've been done better, but not only is Anakin's judgement clouded by love, but also by his friendship with and trust in Chancellor Palpatine.  Prior to Anakin's pledge, the movie clearly showed Palpatine using every chance he could get to make Anakin question and doubt the Jedi Council.  Anakin always had an ego, and Palpatine stroked it well by both offering praise of his own, and recalling and emphasizing the Council's apparent doubt of Anakin's abilities.

The part where Anakin killed Dooku I think was a turning point - Palpatine's social engineering had started to take root in Anakin's mind, and with a simple and rather superficial reason ("He's too dangerous to be kept alive"), was able to gently guide him towards the path of the Dark Side.