What do you think of that?

and What do you think about that?

Isn't that remarkable?; What is your opinion of that? Bob: I'm leaving tomorrow and taking all these books with me. What do you think of that? Mary: Not much. Sue: I'm going to start taking cooking lessons. What do you think about that? Bill: I'm overjoyed! John: Thank heavens! Mary: Fortune has smiled on us, indeed!