I picked up mine 2 days ago. I own an ipad 2 and wanted to try the 8.9 and compare the two. First of all, I love the size and weight over the ipad 2. Although the 8.9 screen is smaller, when playing a widescreen movie you can't tell the difference between the ipad and 8.9 screen size. The 8.9 speakers are much louder than the ipad. One feature the ipad lacks for now that I really like on the 8.9 is the Usb connection kit for $20 at Bestbuy. With my ipad camera connection kit I can only transfer pictures and video. With the 8.9 and the USB connection kit I can playback videos, view Pdf's, doc files, pictures, etc. Basically you can view and/or transfer files to and from the 8.9 to a thumbdrive, SD card (with an Sd card reader) and I'm sure a camera. This makes a big difference in usability.
So what don't like about it? The lag! The ipad 2 has virtually no lag, but I'm sure if it had widgets it would have the same problem. I'm not sure if it's a touchwiz issue or honeycomb 3.1 problem. Basically, as you swipe between screenèss there's a noticeable lag. The lag doesn't appear to affect apps while running, it's just going between screens. Hopefully Samsung will update to 3.2 soon along with fixing the lag with the device.
If you have any questions, please feel free to ask.