A reader of my journal just pointed out that Picutel Smart Resize plug-in is no longer available for download asking me to help in some way. I was surprised to see their website is not working and the plug-in is nowhere to be found. By the way if you know why its development has been cancelled, drop a line.
Anyway after some searching in Google I found a pretty good alternative till the time Adobe release the new Photoshop (hopefully sporting this new feature). It's called Liquid Resize , it's a program and it's based on the same algorithm and work of Dr. Ariel Shamir and Dr. Shai Avidan.
Liquid Resize currently works on Windows and Linux. You can resize both width and height of images, shrink or enlarge, use transparent masks to mark areas that should be protected or removed and basically do the seam carving magic fast and easy.