Just finished viewing Empire Strikes Back, still my favorite movie from the original trilogy, and certainly my favorite out of the entire saga. But did Luke going to Bespin really change anything? It seems that once Lando decides to help Leia and Chewie that they are able to escape, without the help of Luke. Although I guess Luke's arrival on Bespin distracted Vader from Leia and Chewie. It is also interesting that Vader orders Lando to take "The Princess and the Wookie" to his ship, and didn't order one of his officers/troopers to do the task. So, did Luke brashly going to Bespin really change the fate of his friends? Just something I've been pondering.
If Luke had not gone to Bespin and completed his training, Vader wouldn't have been distracted and would have personally taken Leia and possibly Chewie to his ship (unless Boba Fett convinced Vader to let him take Chewie back for the bounty from Jabba too) to force Luke to come to him. That would have necessitated Luke rescuing Han from Jabba first, and then an even more repetitive version of RotJ as they once again storm the Death Star to rescue Leia from the detention facility, only this time they wouldn't have the Falcon since Lando would have totally kept it. So, it would have complicated things. Plus, then Lando would not have joined the Rebellion, none of the pilots would have polished off a tall, cool 40oz can of Colt .45 malt liquor he gave them before the battle (a pre-flight Rebel tradition - see below), and their frazzled nerves would have cost the Rebels the war.
It looks like it stays the same to me. No idea what the brand is, but it's a two word name. Here's the video: http://www.youtube.com/watch?v=0r_GcNJDSg8
The OP basically answered his own question, in the affirmative. Plus, as Locutus correctly points out, no Lando, no beer, no Rebel victory. However, there are other things that would have turned out differently, had Luke not disobeyed Yoda. By the outcome of his duel with Vader on Bespin, Luke observed and realized that Vader wasn't trying to kill Luke, but rather that he was trying to turn Luke, in order to avoid having to destroy him. Empathizing with Vader, understanding his motivation, and realizing that by caring for Luke there was still good in him, gave Luke the key to ultimate victory over the Emperor: turning Vader back to the good side. Further, if Luke hadn't gotten his hand sliced off, and gotten his artificial hand, he wouldn't have been able to empathize with Vader on the visceral level that he did when he observed Vader's cybernetics after the duel on the DSII. This was a big factor in keeping Luke from falling to the dark side.
So that was really why the Empire was after him. Someone needs to splice this together with John Bunnell narrating. http://en.wikipedia.org/wiki/John_Bunnell Drinking and starfightering don't mix. Here a dissolute girl hands a pilot a drink. What's the harm in that? he says. Now three officers try to PITT him in a trench and one cruiser is lost. Later, the kid spazzes out and accidentally fires weapons, resulting in 30 quadrillion credits worth of damage and thousands of deaths. That's right, I'm not supposed to make story suggestions...sigh....
I'm afraid I haven't had the pleasure. Then again from what you people are saying it doesn't sound like there would have been much pleasure.
^Boom! Nice one. Leia, Chewie, Lando and Threepio captured by Vader. Falcon scrapped. Han taken to Jabba. Luke would be on his own to try and rescue Han, if he even ever found out. He'd either get tempted by Vader to attempt a save of his friends alone/with the help of rebel commando npcs or lead the space assault on the Death Star II and probably die since there wouldn't be anyone to convince the Ewoks to help take down the shields. "Luke, know you now why never split the party you should. TPK, you noob. Total Party Kill." -Yoda