I've been using mine for 2 weeks now, this is my first and only tablet.
I love the feel and form factor of the 10. It's lightweight and easy to use with one hand or two, but it still feels sturdy to me. I love that I can pack it around the house with me, or lay down in bed and prop it up in my arms and comfortably watch some YouTube or TV shows on Hulu. The overall mobility is great, and I especially look forward to traveling with it.
I'm happy with the media content. I've been with Android since day 1, so I didn't want to leave behind all the apps and content I've purchased up to now. From what I can tell I won't be missing out on any of my core apps, magazines, movies, etc... I will concede that right now many developers seem to just be blowing up their apps to fit the 10, instead of optimizing the app to fit. I'm hopeful this will improve in 2013.
Performance wise it's been a mixed bag for me. I'm running stock and unrooted with Nova Launcher. 95% of the time navigation and usage is buttery smooth, but it's not completely perfect. I have had issues with Chrome freezing up and causing the tablet to restart, so I'm using dolphin. I've had just a few other times when it's rebooted randomly. Gaming on the 10 is overall a superb experience, however I do have issues with lag and stutter in NFS Most Wanted and on rare occasions in Sword & Sorcery. I am sort of bugged that the gaming experience is superior on an Ipad, but I couldn't bring myself to buy one just for that. All of these things are annoyances at worst - not deal breakers for me. It's embarrassing though to have the system I love have issues like these right out of the box. Again, this is my first tablet so I'm unaware of what the experience is like on other tablets and OS'es and if this is a common thing or not. The positives are that I can use this thing for 3 days and have 6 hours of screen time without having to charge it. I like that.
The screen is fantastic! Prior to receiving my tablet I'd been lurking in the "Damnit, my Nexus has light bleed" thread and had myself half scared to death that that light bleed would ruin my experience with the 10. I do have pretty severe yellow bleed in my corners, but surprisingly it doesn't really ever become noticeable in my day to day use. It bugs me that it's still there and I have requested a replacement on the basis that I expect a near mint copy if I'm paying $400 for it, but I think you can get by most of the time without ever noticing that it's an issue. YMMV. If my next one is bad I might even keep mine because I don't think I have any other issues with it.
My overall experience is very positive. I do wish that the screen bleed issues weren't there and that Samsung actually would have taken the time to calibrate the color and gamma on the panel as well. I'm a perfectionist in my work, so it dumbfounds me to thing that 2 companies like Samsung and Google could release a flawed product, but this seems to be the best choice available to me so I've taken it. My nexus is basically a $400 bedside toy right now, but I love it! Eventually I will transition to getting a bluetooth keyboard and purchase one of the office suite products and use it for true productivity purposes.