Yes, the Bavarian dialect differs from standard German a lot. It has not only to do with different pronunciation, but there are many different words in this dialect. Bavarian is similar to Austrian German, although it is not entirely the same. Austrian German can be understood much better by non-native speakers, as the pronunciation is much clearer.

Having said this, you should not be worried, if you're planning on visiting Munich, as in Munich you will find very few people, who actually use Bavarian, or they will at least speak a very mild form.

You will find that if you visit "smaller" cities in Bavaria, like Passau, the dialect there will be much stronger, and hard to understand not only for non-native speakers, but also for natives, sometimes.

I hope this helps! 

 "Does spoken German in Munich for example sound different from spoken German in other parts of Germany?"

Replace "Germany" by "Bavaria"!  Depending on where in Bavaria you go on your trip, you may encounter people who sound very different from <em>both</em> speakers in the video.

Just like kraut9 says, there are different dialects within the area marked as "Bavaria" on a political map. What you heard in the video was oberbairisch (upper bavarian), which is the best known and most parodied form. Niederbairisch and Oberpfälzisch are similar and considered members of the dialect family "bairisch".

Fränkisch and Schwäbisch are very different from Bairisch and belong to different families.

It's not THAT difficult. Many people will speak hochdeutsch. Also, Bavaria has man outsiders (Z'g-reisste) that don't speak Bavarian. 

But it should be noted that bayrisch is way more common then Plattdeutsch in the north. Plattdeutsch is now even a protected language on the EU Carta.

As a native German speaker from the north I tell you that I have great difficulty understanding some native language 'down there'. Note that there is also not ONE Bayrisch, different regions speak differently.

But even as Northener I find Friesisch 'difficult':

https://www.youtube.com/watch?v=hDJiHSFvm_o

Danke schön! I will visit some small towns in Bavarian and I hope I can understand them a little bit.