The meanings of these two sentences are the same.But the former one is more used in American English(I didn't talk to ya yet),And the second one is frequently used in British English.都是一个意思,只不过前一个是美式英语,美国人有时候也会说第二种(I haven't talked to you yet),第二种一般是非美国人说的,都是完成时。