The Early Adopter: T-Mobile G1
The G1 has an HVGA 480x320 resolution screen that is only still used on low-end Android phones. Most handsets have standardized around WVGA panels of 800x480, or FWVGA 854x480 on Motorola phones. The difference between these screen and HVGA is immediately apparent, and many apps take advantage of the increased crispness. The internals are also much improved in newer phones. The G1 runs a pokey old 528MHz Qualcomm MSM7201A chip. It was slow in its day, but it can't hold a candle to the 800MHz and 1GHz chips being used now.
The software on the G1 is also stagnant. Unless you have rooted and installed a custom ROM, the G1 is on Android 1.6. Due to a lack of foresight by HTC, the G1 was not designed with enough built-in storage to easily accommodate newer versions of Android. Some modders have managed to fit it on, but apparently HTC does not feel it is worth their time. Without updates, users are missing out on important updates like better memory management, Market updates, cloud2device messaging, and browser improvements. This also means no app2sd support, and with that limited internal memory apps storage space is lacking.
Overall, G1 users are due for an update. Unless you love the hardware only for its openness and hackability, it's time for a change. The recently released T-Mobile G2 is a perfectly good upgrade. It is also stock Android, and has much improved specs. There's also an excellent hardware keyboard. If you want to mix things up, The MyTouch 3G Slide or MyTouch 4G are possibilities as well.
The Mainstream Adopter: Motorola Droid
The Droid's screen is still top notch in our book. It's very crisp and bright at 854x480 pixels. You're just not going to find a noticeably better option unless you go with one of the Samsung phones with Super AMOLED panels. Where it is feeling a bit dated is the internal hardware. The OMAP3630 550MHz chip in the Droid was magnificent when it came out, but it's now showing its age. It's easier to bog down the Droid than it should be. The Droid has 256MB of RAM, meaning it needs to close background tasks more often than newer phones do.
The Droid's software has kept up well actually. It is on Android 2.2, which is the newest version. This means its limited internal app storage space is helped by app2sd support. Though some users will still feel the pinch. The Droid is also extremely hackable, with huge modding communities dedicated to it. Even if Motorola stops updating the phone, it can be rooted, overclocked, and flashed with a custom ROM. That will definitely keep it feeling snappy for a while still. You could wait until next summer if you don't mind some work with custom ROMs.
If you're not the modding type, this holiday season might be the time to upgrade. Verizon is usually good about letting users upgrade early with little hassle. Phones like the Droid 2 and Droid X are going to be faster and better supported, but you'll have to put up with the custom Motorola Blur UI. Either would be a worthy upgrade, and the keyboard on the Droid 2 is improved over the original. Rumors of the Droid Incredible HD are also intriguing.
Definitely wait to see what happens in Android Gingerbread if possible; we hope to know those details later this year. If you can get a phone with Gingerbread out of the box, that would be an excellent update. If you want to wait for a big upgrade, hold off and see if any phones drop early in 2011 (keep an eye on CES) with higher resolution screens and Gingerbread.
Last Generation's Hotness: Incredible/Evo/Droid X/Galaxy S
As we mentioned, any high-end phone from the last few months should end up with an update to Gingerbread, but the length of the wait will depend on the manufacturer and carrier. Don't make a move until you see how updates for your phone are going to shake out. You should definitely be fine until about a year after the phone came out. Then you'll want to reassess the hardware space. If new phones are substantially more powerful, you may be reaching point where an upgrade will be worth it.
A word on the Galaxy S phones, though. You should keep an eye on the update cycle. Samsung has a habit of moving on quickly, leaving phones to stagnate (see the Behold II). Given the popularity of the Galaxy S phones, this is less likely than in the past. But if you see Sammy putting the Captivate or Fascinate on the back burner, you might want to consider rooting, or an early upgrade if you're not the rooting type.
We can't say for sure what you'll have to choose from next summer, but our advice will be similar to the Droid. Keep an eye on what happens at CES to give you a read on what's going to be around in 2011. Since your phone is still fairly new, you'll be in good shape through CTIA in the Spring where we should see some more new phones.
As with all things phone-related, your mileage may vary. It could be that you love the Droid and are happy to keep modding it for another year. If not, the Droid may be begging for an update in the next few months. Newer phones like the Evo 4G or Incredible are still great, and you've got time to save your pennies. We don't see an upgrade being necessary until next summer at least. Users of the G1 though, should really look into a new handset. You'll be amazed how far Android has come since you bravely brought that Android home two years ago.
What phone do you use, and what's your time frame for an upgrade?
Images via Motorola, HTC, Flickr user bfishadow