The further south you go, the less pronounced the distinction between s/sh, z/ch, j/q. Speakers of certain dialects will also have difficulties differentiating between "f" and "h" as well as "l" and "n" sounds. So, they might pronounce 护照 as fuzhao or 年 as lian. They might also use different tones compared to proper standard mandarin. And 二话 is little used in the south (although it does some to have a place in 四川话, although I'm not sure about that). As far as I know, vocabulary and syntax would be identical with "standard" standard mandarin. As for Taiwan, although it's pretty close to 普通话, I think it can still be considered a dialect. I have a hard time understanding it, anyways.