No way to tell at this point. I'm still waiting for someone reputable to get their hands on Surface for an extended period of time in order to do an in-depth review.
I think it's all going to boil down to the combination of apps/programs and the usability of the device. You can have the slickest hardware in a world be nothing more than an expensive lump without good programs that take advantage of it. Conversely, having a ton of software doesn't do you much good if the hardware you're trying to run it on is buggy or underpowered.
Too early to tell. I hope it does well - having another healthy, viable option for people is always good for everyone, if only for the competition it engenders.

I use my iPad to read and annotate PDF papers. With its lower resolution and 16:9 aspect ratio the surface tablet is far less suitable for this.
I like the Win 8 visual design, it feels more modern than iOS but in the end it's the use case that matters and from the specs it looks to me that iPad will be the better fit.
There just doesn't seem to be anything that the surface can do genuinely better than the iPad.
If MS managed to create a tablet that handles touch equally well as stylus text input I'd be inclined to give it another look.

iPad 3rd Gen got a proper keyboard-Case-stand, the Logitech Ultrathin beauty

Every time we have seen someone using the Surface the keyboard cover has been used. Does anyone know if the Surface has a virtual screen keyboard as well?
It seems if we want to make an I formed buying decision we will just have to wait until it's released and a review is printed.
Until then I will wait and see.

The productivity focus is a good one. I recently bought an android tablet for business use and it was very quickly apparent that the iOS software is not really up to the task of managing a business device.
Apple may have created the market with the iPad but by ignoring the business users they are being out innovated with things like the surface keyboard and integrated office.

I agree I think I would wait for the release of surface before giving my opinion

This is not even a competitior to the Ipad.. the Ipad is 99% an entertainment device.. this is being marketed as a office users device. this in that department alone will blow the Ipads doors off.
Companies have been waiting for a business friendly MS Tablet that can be managed with their MS heavy environments.
this will sell very well to Corporate clients.

@Fraser " I recently bought an android tablet for business use and it was very quickly apparent that the iOS software is not really up to the task of managing a business device." Android tablets run android os not iOS. Apple doesn't run Android. So what do you actually have? An Android tablet or an iPad?

I will assume that it's as smooth to use as most modern tablets, tegra 3, no lag, etc. I'm not worried about there being less apps, as only about 2% of appstore apps make up for 90% of the downloads and 98% of sales, or something like that. So as long as the apps they do have cover most of the functions I need, I don't really care if there are 400,000 apps I'll never even look at. what maters for me are ereaders (kindle & open source), google maps (unless bing maps are equivalent) or tomtom, since those are offline. ability to put in an SD or microSD card, battery life, web expereince, and then ties into those apps that I do use. Mint, Astrid, etc. but, those apps I do use tend to be in the top 2%. sadly, I don' think they'll cover things like astrid or mint at first. which means I won't be giving up my android devices. and I really don't want to split my devices among different operating systems, making me buy multiple apps, etc. I'll wait for the version that can run x86 software and that might replace my laptop, but my laptop is a powerhouse, so I'm not going to dwongrade there. it might be that they tag low-end pc users, but android/pc users like me might end up too fringe. :-(

I couldn't agree with Jason pope more !
iPads and Androids of the world are all essentially 'entertainment' devices. This is the world's first true 'work' tablet, with a bit of fun thrown in. Just like it should be, just like we all learnt computing in the familiar Windows environment
I am bit disappointed that they launched a 'restricted' version of the OS on the tablet, and I have no idea if that is due to TEGRA 3 brains it has got, but I am super excited. I have waited for this for months. I love the little draw out stand they are providing, and the touch cover thing is inspirational.
Come to India soon guys ! Can't wait ...