After a while using the site now I really like the layout, for looking at a set of my pictures at a glance it's great. However, browsing photos and doing basic things like sharing a bunch of photos on a forum is significantly slower now in my opinion, loading times and moving between photos is quite a bit slower than it used to be.
The weird thing is the raw speed must be there, the Flickrstackr iPad app is still awesome, still much, much better than the actual Flickr site, and much quicker. I can flick through a set of say, 30 photos in probably a third of the time it takes on the actual site.