Apple's (over)hyped ebook-reading, video-gaming, mail-sending, photo-displaying, video-playing wunderkind iPad device has the ability to change the way we interact with the web, in a few ways.

768x1024
I’ll be honest, as a web designer the thought of a 768x1024 screen resolution makes my skin crawl a little bit. It’s an ugly number to look at. It sounds like something that a face smash on my keyboard would produce more than a popular screen resolution size. Nonetheless, it's almost certain that 768x1024 will be the most popular screen resolution size for the iPad.
For those of you who aren't full time pixel-pushers (or full time nerds, like me), "screen resolution" basically means the viewable area on the screen and that area's sharpness and clarity. After watching the iPad demo video and Steve Jobs' introduction of the product a few hundred times, I don't think there is any question that most folks will view the web on their iPads in the vertical position (versus horizontal).
This vertically-inclined resolution will allow users to view more of a website at once while we scan the page to find what interests us. This means that websites (or at least the iPad versions of websites) will get narrower and taller. It’ll be a challenge for designers used to being able to design sites in 1000+ pixel widths for the widescreen monitor masses to restrict their designs to 768ish pixels wide for iPad users.
Hand/Eye Coordination
The iPad doesn't come with a mouse, trackball or anything else resembling a pointing device. You don't need a pointing device though because you already have 10 fingers (or 8 if you are one of those annoying people who point out that "thumbs aren't fingers!"). The “point to click” concept is going to take some time for those new to Apple devices to get used to, but iPhone users should find it pretty familiar. It will also be interesting to see what kind of multitouch capabilities that Apple allows and creative web developers can come up with for the iPad.
A few more web design trend conjectures: buttons will get a bit bigger for those of us with fat fingers to mash on, contextual and highly visible menus will supplant traditional navigation bars that use a lot of flyout menus, and key action items/areas will likely gravitate to the middle of the screen.
Gone in a Flash?
I am hardly what you would call a “Flashturbator” (like my man PT), but it is undeniably lame that the iPad (and all Apple mobile device for that matter) doesn’t support Flash. Steve Jobs thinks that Adobe's Flash product is buggy and that HTML5 is going to somehow supplant Flash, but having Flash on a mobile device that holds itself out as having the best mobile web browsing capabilities around seems kind of like a no brainer to me.
How this will affect Flash development and its popularity and use on the web remains to be seen, but Adobe and the people who develop Flash for the web have to be more than a little vexed that Apple’s popular mobile devices like the iPad don’t support it (much less the fact that a turtlenecked cult leader CEO like Jobs is basically calling them lazy asses).
Surfin' Safari
Will the popularity of the iPad and whatever version of Safari it comes with translate to a greater share of the “normal” browser market for Safari? Probably not.
For “normal” web browsing (i.e. on a desktop or laptop), I see Internet Explorer 6 (I just threw up in my mouth a little...), Internet Explorer 7, Internet Explorer 8, Firefox and Chrome continuing to dominate Safari in the traditional web browser popularity rankings, despite it’s web-standards compliance and miscellaneous “cool” features.
However, Apple and Safari can take solace in the fact that more and more people will be accessing the web away from their desktop/laptop, and those people will most likely be using an iPad (or similar Apple mobile device) to get on the web. That means that Safari will continue to gain share. What a greater share of web users means to Apple’s bottom line I don’t know.
A Shift
All this speculation is one thing, but none of us will know what the true impact of the iPad will have on web design until millions of us get them in our hot little hands and start using it. As someone who pays more attention to web design and web surfing trends than the average person, it is exciting to see a device like this come out that has the ability to make a shift in the way people interact with information online.
Back to the future anyone....
john