Be careful when plugging it back into iTunes for syncing, iTunes will know that app shouldn't be there.
One easy fix is to deselect the ability to sync apps with iTunes. I checked the box and the downside is I have to manage the install of Apps myself. No biggie.
It works great on my 1st Gen, really enjoying it (apart from some aspects of UI). Same goes for 3GS too.
Really cheeky of Apple.
I don't think it is cheeky of Apple at all. This is a comment I made on my blog as to possibly why Apple didn't allow iPhoto to run on the original iPad:-
I can't really fault Apple for not letting iPhoto run on the original iPad. It does make sense to restrict iPhoto only to devices with cameras. Besides the geeks, who else is going to go through the effort of getting iPhoto to run on something it's not meant for? My first thought was to take advantage of the larger screen for photo editing; taking full advantage of Photo Stream to transport images back and forth between devices.
Imagine if iPhoto could run naturally on the original iPad. You only have to look at the average pile of comments accompanying Apps on the App Store by those who complain with a 1 Star rating about the slightest thing they don't like with an App. I think Apple saved themselves some hassle justifying it's existence. Geeks on the other hand are going to understand installing another piece of software, (iPhone App Configurator) the limitations of running it on an older device and just accept them, like I have done.
I'm not trying to apologise for them, I think it makes sense on their part.
Hope this makes some of you happy to see this.