What are the major differences between Belorussian and Russian?

Belarussian language is close to russian, but the major difference in pronunciation. I think that belarussian language more beautiful, more melodical. And belarussian language alike with ukrainian very much! 

The funny question is -- do you think Russians would agree that Belarussian is more beautiful and melodious?...

That's interesting.  Can Russians essentially speak Belorussian?  Are the differences more like American English and British English?  Or are the differences more like Spanish and Italian? 

the difference is that belorussians live in Belorussia, and russians in Russia. Belorussian, russian and ukrainian are pretty similar languages. They have almost identical grammar rules and orthography. But.. but they are still different languages. With different words, letters. It differs much than US from GB. Our languages are older then US, so I can suppose that sooner or later US will less look like British english. If you're a ukrainian and you lived some time at Belorussia you WILL be able to understand everything you hear, and speak in a "not that bad" way.

 Ukrainians will understand belarussian, but russian people will understand not all. Our language is called "trasyanka"(трасянка)-it means russian+belarussian language, thats why russian, belarussian and ukrainian alike.

meow )

Rusiian is more beautiful than Belorussian, I believe ^__^
and it is developed better )

yes, Russian, Ukrainian and Belorussian appeared from Old Russian about 500 years ago
BrE and AmE parted not as long ago
and I think that Spanish and Italian appeared about 3000 yrs ago (not sure about it, but it was long ago)

decide yourself, which are closer

Russians cannot understand Belarusians but Belarusians can understand 90% Ukrainian speech, and about 75% Polish speech. Most Belarusians also speak Russian, although (arguably) they have a version of their own called trasianka. The trasianka is generally looked down at by more educated people.