Sync Solution:
I do not use MobileMe, I also use Google for PIM. The best way I have found to sync Contacts is with the app 'Sync in a Blink' from the App Store. It is $5 but it is well worth it, it does a great job.
For Calendars, I use NuevaSync. It's an online service you register for (free) that will allow you to sync Google Calendars to your phone. You have to register and set it up on the site first:
NuevaSync - Over the Air Synchronization
It has step-by-step guides on the site. It will also allow syncing of contacts but I heard it syncs fine from Google to iPhone, but when changes are made on the iPhone, Google will ignore the change if the contact has no email on their information. After hearing that, I never tried it for contacts and found another way. Feel free to try it :P
Gmail is easy for email on the iPhone, it's right in the Setup app, and it's IMAP.
Favorite Apps:
I've jailbroken my phone so I can list so many, but if i am to stick with non-jailbroken ones, a few that come to mind are:
-Google Mobile App (of course you've heard of it)
-Evernote (sync text/photo/voice notes to the cloud)
-WeatherEye for weather
-AroundMe to find things around you like restaurants
-FieldRunners is a great game
-Ocarina is a must try. Go to their website to learn the music:
Ocarina
..There are tons.
Today screen:
There is an app called Intelliscreen that will show Emails, SMSs, News, etc fully customizable. It's only available on jailbroken phones though
Battery saving
-Turn down the brightness
-Turn GPS off until you use it
-Lock screen set to 2mins or less
-Wifi off until you use it
Jailbreaking fills a lot of voids that people complain about, but i'm assuming you're not allowed to do it
. Either way, thanks for participating in this Round Robin. I'm really loving the reviews and it will be helpful to many many people. Enjoy the phone like we all do!