That being said, if I had never used an iPhone, the G1 would be great. It has a bunch of decent apps and is fairly easy to use -- at least compared to the BlackBerry and the user-unfriendly software found in Windows Mobile devices. Still, every time I pick up the G1 and use it, I really wish it was an iPhone.
The device feels vaguely iPhone-ish, though with a more complicated applications and menu system. It has a bunch of the same features as the iPhone: 3G (although T-Mobile's next-gen network isn't as large as AT&T's, it worked fine in my neighborhood -- something that can't be said for AT&T), GPS (the Google Maps app is nice, but it's slow to respond when scrolling or zooming), plus, of course, Web browsing and email.
The physical keyboard is nice for people who want it, if you like the candybar form factor with a slide-out keyboard. The mechanism for flipping open the phone seems a little fragile and I wonder how it would hold up to long-term use and abuse. Like the BlackBerry Storm that just arrived from my stogie-smokin' FedEx man, the G1 takes way too long to rotate from horizontal to vertical. Annoying, but not a deal breaker.
As a music player, the G1 is not an iPod replacement. I have completely abandoned my iPod Nano in favor of toting just my iPhone around, and it works fine. I would not be able to do that with the G1. The G1 turns to Amazon's music store for support, but considering iTunes is what most people use to manage their music collections, the G1 just doesn't cut it.
Clearly, the iPhone has really raised the bar for every other smartphone. If I had never seen an iPhone, the G1 would be fine -- but I have, and the G1 just isn't the same. It's slow, it's kind of chintzy, there aren't nearly the same number of applications, and the media support is unimpressive.
The device is unpolished. It feels like what the iPhone probably was 5 iterations before the final version came out -- version 0.3. Steve Jobs would never have shipped this phone.
Some of my complaints can be attributed to the fact that the Android platform and the G1 device aren't well integrated. Android is meant to be run on a wide variety of phones and devices, and the G1 implementation just isn't as strong as it could be. That said, competition is good is good for consumers, and an increase in the number of smartphones on the market will lead to better features and services. Hopefully, the G2 will be better -- but I don't see anything replacing my iPhone anytime soon.