I think the pitfall here is how this particular feature is 'classed'. When you say something is 'necessary' or not, then you get very2 subjective.

ie: Is it a necessity for anyone here to own a 7 or 10" internet tablet?

Generally I agree. But the distance can vary a lot and there's one more element here that I think is crucial, which was the saving grace of past iPhone\Touch's low ppi screens:

- Zoom capability of the OS. (How fast, how easy, how available)

Yes, because you're comparing a 4:3 screen with a 16:9 screen. It's not a direct ppi comparison, you're unnecessarily introducing another element in this comparison.

I did upgrade my 3GS to iPhone4 and I was quite informed and I was still pleasantly surprised and happy with the increase of ppi. It was really useful; for example to determine if the pictures I've taken was properly focused or not.
Although I admit that I'm still Apple's bi+ch.


Subjective. People may mistake this to you having less sensitivity to high quality picture or having low standards.

You forget that the general limiting variable here that limits viewing distance is the user's hand. You don't artificially stretch (and sprain/discomfort) your arms just because you're holding something bigger.

iPad's resolution is not bad, but I am quite certain Jobs will put retina-class display on the next one. I certainly could use a higher ppi on the iPad when reading publications (ie: zinio) on it.