go to Start > Setting > System > Version

The latest one should be i900DXHG4

Mine is G3. I noticed that some of the features that someone mentioned from PPCSG already in G3.
- Hactic Feedback Lesser, only launching something will have feedback. (No vibrate when typing)
- Samsung Today 1 Plugin
- Smart Reader
- Changes to Calculator Skin
- End Key Function to lock Device

I'm not sure about below items:-
- Overall Speed Faster
- Some icons are changed (like when charging, Calculator)
- Orientation are better in G4
- More Video Settings
- No change in Memory

This one for sure
- New Input like Samsung Panel and 点讯输入

You can download it from here
http://www.samsungmobile.com/promotion/omnia/index.jsp

Our version 3 has most of the items - except the Chinese software I think. We have all the stuff like BizCard Reader, New Icons & today pages, etc. So an upgrade may not be needed. Anyhow - I don't think it will void any warranty as it's a software upgrade and you're not fiddling with the hardware. However if you are using Windows Vista, be careful - a lot of people having problems upgrading their phones.

chinese input is included in G4. Just updated my omnia to G4 and i notice that to lock/unlock the phone in G4, we need to press the lock/unlock icon on screen whereby in G3, we just press end-call button will lock and unlock the phone.

Finally, i managed to installed Garmin Mobile XT on it and it is superb. The satelite locking capability is good , fast and accurate...  

I put my garmin in my storage (omnia's internal memory)...I will share the steps with u...no worry....

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Added on August 13, 2008, 2:17 pm
I am using Garmin Mobile XT 4.20.50w (https://buy.garmin.com/shop/store/downloadsUpdates.jsp?product=010-11034-00&cID=138&pID=11413)  and pair with Malsings map GM-MySin Jan 2008 (http://www.malsingmaps.com/portal/)....  Garmin Mobile XT works very well with our Omnia internal GPS receiver. So, you do not need external GPS device...

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Added on August 13, 2008, 2:24 pmwhy don't we have a list of proud Omnia owner here....lets see how many of us.   let me roll the ball...
1. [Sukhoi35mk][10-Aug-2008][Ori][RM2799][black colour..   ]

keeekeee yours is 8gb version or 16gb version?the 8gb micro sdhc is what class ? class 6?how much you bought? 

3)ericchan 8gb(version)+8gb micro sdhc (G4 firmwear) fmg set metal black

morning everyone just collected my freebies from samsung yesterday i have collected the leather pouch screen proctecter and the digital photo frame actually is just a normal photo frame nothing special and about the tvo cable it will be arriving on next month possibly around the 10th so be patient ya..

it looks like this bro 
picture by the samsung omnia i900 

hi keeekeee pls try ZTA4.. it's a freeware and easy to use oso.. no prob at all..

hi guys if you all want to flash the h1 firmwear by yourself this is the side you can download http://www.mediafire.com/download.php?2ctayvcvex2

i have download and flash it this morning now the whole omnia's just like lamborghini reventon!

i dont think that there is a real rush to go and update the firmware at the moment. the G3 works just fine for me at the moment. But i will upgrade in the future. Samsung will come out with many many more new updates, which is usual for a new model, cant get everything right the first time. So wait and see....

if the update contains something u really really want, then by all means go get it. Otherwise just wait a month or two for things to stabilize and settle down and then get the latest firmware..