I had a 5 series (LCD revision code, most people know what I am referring to. Tutorial at the end of this post) While this is the LCD rev number, it also says a lot about the phone. I gave my 5-series phone to a relative who didn't have them in their city, and got myself a new one. The second time around I got a 7 series and I'm not as happy with the overall build quality. The screen is dimmer, it is more likely to have visible white grid spots, and there is a better chance that the black plastic backing squeaks or shifts. While a 7-series owner may not experience all or any of these problems, I have all 3 maladies... although my white spots are not as prevalent as other ones I've seen. Is there a way to tell if you have a 5 or 7 from the outside of the box before its opened? (I doubt it). Also, are there more 5's made than 7's or vice versa. FOR NEWCOMERS, to find out what revision your phone is, go to the phone pad and dial *3001#12345#* and hit "call". Go under the "version" menu and see what the first digit is in your LCD number. 5 is preferable.