-First, welcome! I came from a Blackberry as well.
-Complete the Swpe keyboard tutorial. It takes a modest amount of practice but once you get used to it, you'll be delighted by how efficiently you can input text, which will largely determine whether this phone is one you can actually live with--especially if your BB had a physical keyboard.
-Have fun w/the Android Market but be aware of the permissions you're granting while installing.
-Give your Touchwiz launcher a chance. If you don't like it, get LauncherPro or ADW.
-Read-up on LauncherPro plus, consider upgrading. The developer is great, and updates often.
-Read up on rooting if you have the courage and want to get rid of/hide bundled apps. It's not difficult, but it's not without risks.
This should get you started well on your way. Enthusiasts (folks who lurks/post in forums) are turning purple in anticipation of the 2.2 ("Froyo") update but honestly, coming from a Blackberry Curve 8330 running BB OS 4.2, this device blows my mind even on its current software build (2.1 "Eclair"). There's certainly still room for improvement (particularly on Samsung and Verizon's part), and the new gmail app will be nice, but it's already a superb device imo. Have fun!
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