I agree with Brown's thoughts that powerpoint can become a problem when there are too many distractions or too many words on the slides. Teachers obviously need to model how to use powerpoint with their students and give them clear directions and rubrics around any presentations that the students do with powerpoint.
For me personally, I haven't used powerpoint in my teaching, but I am open to it or another presentation tool. My biggest concern with students using it is the language barrier and the time commitment. Because my students are English language learners, they would need to be guided through the use of powerpoint quite slowly and carefully. That could take up a lot of valuable time in our short and intensive semesters. We only have 32 classes in a term, so that is about 6 1/2 weeks.
Secondly, my students don't do a lot of research projects, but I could see how it could be a useful tool for a 5W-H summary of a newspaper article in a local newspaper like the Surrey Leader in my Reading 3/4 class.
Doing more presentations would definitely help the students to gain confidence and to improve their public speaking ability. As Brown correctly points out, it would be essential to teach the students not to read from the powerpoint but to use it to organize and summarize information.