As promised, what follows are my impressions after two weeks with the phone.

Pros

• The built-in camera has a resolution of 640 x 480, and is way better than the pitiful, why-even-include-it camera on the T616. Of course, the T616 was old when I got it 18 months ago...
• I like having MP3 ringtones. On the night of July 27th, I launched Audio Hijack Pro, and captured, via iTunes, the first 20 seconds of The Who's "Baba O'Riley." This is now my default ringtone. (To show you what a super guy I am, if you want it, here it is, saving you the time and effort of doing it yourself.)
• The screen is bright and clear, even at the default settings for brightness and backlighting, which I have yet to tamper with. The keypad is easier to use, and I much prefer the five-way navigation key to the joystick employed by Sony Ericsson.
• It has worked flawlessly with my SE Akono Bluetooth headset.

If you want to remain in good-news-only bliss, then don't read the cons after the jump.

Cons

• While the v551 works flawlessly with my Akono headset, I also hear every single sound the phone may make through the headset. Boo. Hiss. I only want to hear the phone call, not every key press. Your phone should make this distinction when in use with a headset system.
• Also, when the headset is in use, whatever ringtone you have set for the phone is replaced by a generic, beeping ringtone. Again, boo. Hiss. What difference does it make to the phone, ringtone-wise, that the headset is connected. The headset has its own bland ringtone. I don't need another one. This means that so long as I have the headset connected, no one can hear the cool, aforementioned MP3 ringtone I made.

The Deal-Breaker

What ensures I will not own another Motorola mobile phone, though, is the Phonebook.

Now, I was not plagued with the inability to sync the v551 with my PowerBook, like some have experienced. Once I deleted the pairing of my old phone with the PowerBook, I was able to pair and sync, via iSync, with no problems whatsoever. The problem is with Moto's Phonebook implementation, and yes, I will be comparing it against Sony Ericsson's, since that's what I'm familiar with.

If you have stored contact info on your SIM card, as have I, the v551 displays this info with no problem. If you happen to sync your computer with the v551, however, it does not update the SIM card, but rather loads all of the contact info in to the phone's memory (a decent 5 MB). You then have, in the Phonebook, the same information listed twice. Except the SIM card info displays by last name, first name. The info in memory displays by first name, last name.

With no way to only have one or the other display.

I went through every menu. I read through the owner's manual. Finally, I contacted Motorola technical support. Here's what I sent to Moto:

I recently received a Moto v551 as a replacement for another phone I had through Cingular. I took the SIM card from the old phone and placed it in the v551 with no issues.

I am a Macintosh user, and have been using Apple’s iSync software to synchronize contacts from my PowerBook’s Address Book with the v551. However, it appears I am getting double entries. The sync puts contact info in the phone’s memory, which is fine. But the v551’s phonebook shows both contacts in the phone’s memory, and contacts on the SIM card.

Is there a setting on the phone to tell the phonebook to only use contacts from one source? I would like to use the phone’s memory, and not the SIM card, but I would rather not delete contacts from the SIM card.

Here's what Moto sent back, with the generic stuff edited out:

Regarding your concern, when accessing the Phonebook menu on the Motorola V551, Phonebook contacts saved into the telephone memory and into the SIM card will be automatically displayed. Unfortunately it is not possible to disable this feature.

In February, I'll be eligible for a phone upgrade with Cingular, or I can go to May and switch services, should I choose, when my contract is up. My next phone will certainly not be a Motorola.