Is there really any difference? My friend speaks Croatian and claims that Serbs won't understand her if she speaks Croatian without using Jugoslavian vocabulary. I wonder whether that applies to Macedonian vs. Serbian.
Actually, the language is Serbo-Croatian. So that's an absurd. I understand Croats. What's more, there actually different lines of dialect divisions, than Croatian-Serbian; ijekavski and ekavski, and štokavski, štakavski and kajkavski (the most basic ones, there are more), and some of these dialects are spoke by both, Croats and Serbs.
After the collapese of Yugoslavia, mainly Croats and Montenegrins have been trying to introduce their own vocabulary; I remember one of my cousins having volumes of Harry Potter both in Croatian and Serbian (it depended on which was published earleir, and then she bought the certain edition - Croatian or Serbian; so you see, no problems in understanding), and in Serbian edition the broom Firebolt
was translated as "Vatrena munja" and in Croatian one as "Vatrena strela".
Surely, there are some real differences in vocabulary, but you can say it also e.g for Polish or any other language.
However, the difference between Serbo-Croatian and Macedonian is bigger, as the grammar is different, that's the most important thing. But there is one Macedonian living in my housing estate and we don't have serious problems to understand each other.
It's been a while.