A bar is not always a bar!

The # of bars shown on your phone indicates how good a signal you're able to receive, but there's a HUGE difference in what 1 bar means from phone to phone.

Apple has cleverly scaled their bar indicator to make it look like the iPhone 4 gets better reception than other phones.  Standing in the same spot, holding an iPhone and an Android, you might be impressed by the iPhone showing 4 bars and the Android showing 1 or 2.

But hold on a minute!

My Motorola Droid shows 1 bar right now, and in the details I can see that that's a signal strength of -85db.

Look at the iPhone signal strength-to-bars chart on this page...the iPhone would be showing a full FIVE BARS at this same strength!

The real answer is in whether or not you can make (and not drop) a call.  And we all know how the iPhone 4 does in that test :-(