Not at the moment, no - we're a little reluctant to do it totally automatically because it's really hard to capture intent effectively with flashcard history; people look up a LOT of words they don't really consider themselves to have looked up.
You can however dump all recently looked up words in history to your flashcards via the History screen.
You can tap on a word in the history list to view it as a dictionary entry and then tap the + button to add it to flashcards as with any other dictionary entry. (And scroll through the list with the arrow buttons at the top)
We might add a batch mode to that screen at some point to let you tap on a bunch of words to select them and then add them all to a category at the same time; would that help?
Adding a batch mode would make a big difference. I/we spend a lot of time adding words to our flashcard files, a batch mode would be a big time saver. Flashcards are an integral part of our study/learning process. (How many people have purchased FLASHCARD upgrades). Just making that process easier/more convenient would improve the process.