[sunNsnow]

Calendar: if you use Google Calendar, you can create shared calendars and separate calendars (kids' schedules), etc. I love it because I can create an event using my PC or with the phone and it's all there without syncing. The phone syncs with your Gmail account.

There are lots of free apps but they come with advertisement, etc. You have to read through the permissions the app needs before installing... some may want access to SMS/MMS capabilities (spam alert) etc. Not that all free apps are like this, but you need to be more aware of what you're permissions you are giving the application before installing.

Backups of your contacts and calendar are through your Gmail account.

Swype ships with the X. Typing on it isn't bad either in landscape mode since you have a large screen to type on (the virtual keyboard is wide and comfortable to type on).

As for customizations, you can customize it to a point. The X -- I believe -- has been rooted ("unlocked") but I have not done this to the Droid2 yet. The X and Droid2 has some sort of security chip on it that makes rooting an interesting experience, from what I've read. I am proceeding with caution in this area.

Emails: I recommend using k9 Mail rather than the mail program that comes with it. You no longer need inbox extender.

Hope this helped.

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sunNsnow