IMHO just the former, at least in this first generation of the device. I don't really see anything that it can do which other devices aren't already better at, and massive drawbacks.
The integration with publishing houses is a nice feature, but i don't quite see this becoming a huge market. ePublishing of magazines and newspapers has been tried for more than a decade, yet calling it a niche market for anything but academic literature would be an euphemism.
A fully integrated environment which makes it easier to download magazines and newspapers won't make such a market viable on a large scale, IMHO...for if that were so, then online publishing already would hold a significant foothold at least among the tech savvy people who aren't scared away by having to download something (usually PDF) and then to view it with a seperate program.
The aforementioned drawbacks:
1. Lousy screen resolution.
Keep in mind, this thing is in direct competition with netbooks, so netbooks set the standard here. For a netbook in this price category 1366 x 768 is the standard, and this can play 720p videos without downscaling. The iPad only offers 1024 x 768.
2. No multitasking.
For a phone or music player this may be acceptable, but when i use something for comfy webbrowsing at the couch, then i want it to be able to run a mp3 player in the background, or to play a webradio. This alone already removes the iPad from the list of devices that i'd consider for mobile web browsing for me.
3. Low storage capacity.
It's supposed to play (downscaled!) HD videos, yet it only comes with 16 to 64 GB of storage. And streaming HD video won't really be an option on a large scale, at least not for quite a while.
Besides, the price policy regarding memory upgrades is just a huge rip off. For that reason alone i'd boycott it.
4. Lousy connectivity to other devices.
5. No Adobe Flash.
At least not directly integrated into the main browser.