I saw some Pecha Kucha talks a month or two ago, and got the feeling that the extra length, as compared to the Ignite format, didn't help.

It seemed odd that an extra 1 minute and 40 seconds would make any difference, but Ignite talks seems to have more pep, perhaps because the slides advance 5 seconds faster.

But both formats are hard to do well. Too many presentations end up being a list of items matched to Flickr images and Helvetica-rendered slogans or quips.