Had my surface for a week now, and totally loving it. I went for the 32Gb version with touch cover which I'm using to write this on my lap at the moment. Perched on my desk I can type as fast as on a proper keyboard, on my lap it's a little slower because your hands fall in a slightly different place so need to get used to it. Still heaps faster than using an on-screen keyboard though.
If I had to sum up my experience so far, it would be that I've had to change the way I think about using a computer. Suddenly I miss not being able to swipe the screen when I'm using my desktop. It took a while to get used to but now I have, it feels really natural. I also had to rethink how I thought about my Surface. It's so easy to compare it with a laptop as it's so capable in it's own right and the touch cover reinforces that feeling. It's the wrong comparison to make though, as it isn't a laptop, it's a tablet and cant match the flexibility of a full laptop... If you do that, you'll be disappointed.
Compare it with a tablet though, which is the correct comparison to make, and you'll be blown away. It's like a tablet on steroids. It does all the stuff that any other tablet ( ios or android ) does, and then just keeps doing more. Full integration with my Xbox and desktop account, ability to work with all my documents that are saved to SkyDrive using MS office, map network drives on my desktop to stream media ( and will now play MKV files using in store media players instead of faffing around converting ). I could go on and on.
I never used to carry a laptop everywhere, but I have started using my surface that way. Apps for the trains, tube etc... all have live tile that show me at a glance how my commute home will be.
I'm not a Microsoft evangelist, but I have to give the credit where it's due. This is a nice product, well made, excellent design and concept with all the essentials and many other touches added such as the USB and HDMI connectivity...
I work in IT ( for too long now !!! ) and I think that with the right marketing by MS, this could replace the trophy Ipads that many of our senior execs asked for and then left in a drawer because they couldn't do as much with them as they thought. Make no mistake, this is a true productivity device for the office, as well as a great tool / toy for home use.
I was planning on waiting for the surface pro, but after some thinking realised that effectively, it's a laptop and I already have a nice one of those. This bridges the gap beautifully. Windows RT isn't as fully functional as full windows 8, but for a tablet, the "omissions" seem hard to find, and it's still way more functional than say, an Ipad.
As for the numbers of apps, it's a personal thing. I had an iPhone and installed about 10 apps on it. I now have a windows phone and have the same number of apps. I have found everything I could want or need on the app store for my surface so far. If you absolutely have to clog up your device with millions of apps, then at the moment you might have to wait. If you're like me, then you'll find all you need, and be comfortable with the fact you might have to wait a bit for something ( PayPal is an example... not on the app store at time of writing ).
My final comment... If you're an apple / android fanboy, then this probably wont be your thing, but to anyone else, I'd say try it, and be amazed. If MS start putting these into the shops, then every other tablet manufacturer better be afraid.