Motorola's Droid 4 and Droid 3 are obviously very similar, but the main difference is that the Droid 4 is 4G LTE capable and shaped more like the Droid Razr with cut-off corners and slightly curved edges.
Both feature 4-inch qHD displays, 8-megapixel cameras and sliding physical keyboards. The keyboards are nearly identical. Both are of the back-lit, five-row QWERTY variety, but the Droid 4's dedicated number keys at the top now feature alternate functions as well as their main numbers. It's the opposite on the Droid 3 where the letters have the alternate functions (pound sign, ampersand etc).
If you're upgrading from the Droid 3, it might throw you off initially, but most others won't notice the difference. Besides, there might not be that many people upgrading from the Droid 3 because it's only been out for less than a year. For now, both are priced at $200 on contract from Verizon, but when the Droid 4 goes on sale Friday, the Droid 3 could go down a few dollars. There's no official word on that, but it does seem logical. Droid 4 will also feature a 1.2GHz dual-core processor, Android 2.3, mini-HDMI port, 1080p video capture and can plug into one of the LapDock accessories that turn Droids into notebook computers.
Motorola promises to bring Android 4.0 to both the Droid 3 and four, but the timetable is not set. It could be a few months for each, unfortunately. Furthermore, Droid 3 came with Swype pre-installed, so we're assuming the same thing for Droid 4, but tech blog Slashgear did a hands-on (not a full review) and Swype didn't seem to be on there. We'll have to wait until we can get a full review to find out.
Tell us in the comments if you like physical keyboards and what you think of the Droid 4.