Dr. Harold Koplewicsz states that girls have better language development while the book Beyond Baby Talk: From Sounds to Sentences, written by two speech-language pathologists, say "research that has examined whether boys and girls understand language differently has consistently yielded no (significant) differences".
Expressively there are slight differences in expressive language, e.g., girls are more likely to use more words related emotions than boys do.
Apel and Masterson also state that girls typically use language to work with peers to solve problems earlier than boys. Preschool boys seem to work through more problems with actions and over time begin more problem solving with words. Whether problems are solved with actions or words, the success that boys and girls have with problem solving is similar.
They also state that girls tend to initiate more turns in a conversation than boys, use more nouns and have clearer speech. The slight differences in general language development between boys and girls are not problems, when the goal is the same...language development.