Centered on Ovi.com, the Nokia Ovi (Finnish for 'door') is your "personal dashboard" to stay updated, connect and share from anywhere,anytime. It enables users to tap into their existing net communities and content, social networks and allows easy access to the Nokia services. The Ovi also provides a doorway to access third-party services like Flickr. This is a major move by Nokia into the Internet services domain.
By creating a Nokia account, you can access the many features supported by it, both on your pc and your mobile.  Download the Nokia Ovi Suite and organize/share your PIM data and photos between your mobile and pc comfortably. 

The "Ovi umbrella", offers the following services:
Share On Ovi : Connect easily with friends and family by sharing whatever you dig...images, songs or videos easily and quickly from mobile using the share on-line app or from your pc . The service is free although the data charges may apply. A 100MB max file size is limited though. Share on Ovi, initially called Twango is a media sharing site.

Contacts and Calendar: Never lose touch with your friends and family. Have their contact details, your appointments or meetings backed-up and synchronized on ovi.com.

Files On Ovi: This allows you to access the files on your pc from a mobile device or a remote pc anywhere.

Ovi Maps: With the Nokia Maps re-baptized as Ovi Maps (and the vector map data totally updated), planning you trips and synchronizing your routes becomes as enjoyable as a holiday trip is meant to be. Find you way around over 200 countries using the maps which can be downloaded via your mobile or your pc. If you're a maps-freak, then pre-loading them will cost you less in terms of data transfer over the network.

Ovi Store: Always have the latest apps and content at your fingertips. Get the latest games, videos, apps and lots more at the Ovi store.

Ovi Sync: Always have your notes, contacts and calendar synchronized and backed up on ovi.com.

N-Gage: Try out new challenges on the latest N-gage games or buy games for your mobile. In India, the N-Gage Arena has gone live since May. Even during the "no-game times", the arena Clubhouse is open for gamers to just hang out and socialize.

NokiaOvi Music Store: Listen to the latest songs on Ovi Music, and if you really love them you can directly purchase them. The Ovi genre-based play-lists and dynamic recommendation engine are pretty neat.    

Ovi Mail: All Ovi users can enjoy the e-mailing services offered by the still-in-beta Ovi Mail. Currently more than 40 S60 and S40 based models support the new mailing services by Nokia. The Ovi Mail has become pretty popular among it's users. Just create an account on ovi.com and you're set to go.   
Put these all together, and Ovi spells to the message that no matter where you are, Ovi is your doorway to your digital world.

Flaws:
The Ovi interface is more like a simple browser rather than what you'd expect for a real application as Ovi is claimed to be.
The Nokia Ovi suite takes a lot of time to sync and the first sync seems to take ages. Your patience is bound to be tested!
When you browse through the applications list in the Ovi store, you come across many apps that are no longer available for download. They have been removed from the store but somehow they still get listed in the available downloads!
The user experience is NOT smooth. The on-line store navigation is too complex, and even gets irritating.

Buzz on the web:
Reviews like "They made too much buzz over it..", "...too bad i wanted to sync with Ovi" REALLY doesn't sound too encouraging to dive head-long into it. Although there are quite a number of reviews that compliment the Ovi, the majority of users don't seem very happy.

Final Whisper:
The Ovi offers a lot of possibilities and is an application that more than just syncs devices. Some of the features to sync contacts and calendars, files, and it's personalized form of social networking are indeed attractive.The calendar and contacts capabilities are pretty neat and can be easily compared with ActiveSync.
However, all the buzz that was built for it seems... over-emphasized and what has been served really doesn't come up much to it. I personally feel that Nokia themselves made it too hard for Ovi. However, let's give it a little more time and see how long it takes for the Ovi to get stabilized. Until then... explore without too much expectations.