I used to own the W800i (Walkman) phone. I loved everything about it, but the K790 / K800i phone is EVEN better:1. bigger and brighter screen size and higher resolution. As a result, the phone is slightly larger than the w800i but the benefits outweighs the size increase. The icons are bigger and clearer. Font size is increased so it's much easier to read text messages. You can now surf the web (not just mobile web pages.) Being able to display the photos on a larger screen is great.2. I LOVE the RSS reader. With a click of a button, the phone updates the latest news from BBC and Google news and SONY news and updates. I just skim through the head lines which are linked to fuller articles on the websites. This is great for me who commutes on the train every morning. Great time killer standing up or sitting on the train.3. Walkman is still great. It's not as buggy as W800i. But there is no more MegaBass. It still sounds great. Unfortunately, the phone does not come with memory card. I had to buy one M2 (Memory Stick MICRO) which I had to wait about a month to get since it's really new and not many stores have them in stock. So if you want to fill up the phone with songs, built-in 64MB will not be enough.4. The camera quality is excellent (for phone camera, that is). I am very particular about digital cameras and picture quality. I find that this camera is overall not as good as a basic, stand-alone, cheap 3 Mpix cameras that are cheaper. HOWEVER, it good lighting condition, it takes great picutres. There is definitely more noticible purple fringe and digital noise than a dedicated digital camera. In low-light condition, even with the super bright flash light, the picture quality is sub-par. There is too much noise. The metering on the camera is so-so. If there is a strong lighting constrast between your subject and the background (such as bright windows), I find the camera has a hard time balancing the light--making the subject too dark. The ability to have a portable camera with me at all time, out weighs all the imperfections I get from it. As a graphic designer, it's important to have access to a camera at all time to grab images for design inspirations.5. I am curious to start the photo Blog--a built-in feature in the phone.6. Games look great on this camera. 3D games like MiniGolf and Tennis which came with the phone are amazing.7. Built-in ring tones and background screen/wall paper sound and look SO much better.8. Email function works great. I have a dot.mac account and can view and send emails without problems. Right now, the phone does not support flash player so I can't view any .fla files. I don't really care but sometimes websites do require that flash player is installed.This phone has amazed me and impressed me beyond my expectations. I hope more of my friends have it so that I can try to video phone function!