here's a simple tip to sync/export your contact if you don't have external sd or not able to export to sdcard.

Open your contact, select 'send via' then select all, and then choose your email address to send to. This will send directly a .vcf to your mail and if its google mail, then use your googlemail to import the vcf into google contact.

Next you can sync your google contact with your phone in any event that your contact disappeared from the phone.

You can also use trafficstats lite to monitor and check which applications using your bandwidth, wifi or 3g.

Here we go again. Same as P3 to P4 to dual core to quad core to lost count cores.
Then, none of the apps can take advantage of the cores till much later. Hoping that android apps are multicores ready. If not, at least multi-core smart to distribute the app to run in unused core.

Get the quality one or don't put also ok. SGS has one of the toughest screen ever made for mobile device.
It won't be easily scratch. I've used 3 months put in pocket with all the coins and no scratch. But I have the cm case covering its back. And I feel the plastic cover disrupt your touch and movement on the screen.