After using it for long time, I discovered some good things about this Phone. The Phone works best when you have a GPRS connection.
The things I like:
I can configure my Yahoo! and Gmail account.
Even Outlook can be configured if your company has some allows it.
I found a free facebook widget.
It has GPS which helps me a lot. I use it with google maps.
Can save some txt, pdf and doc files for later read.
Now I can say it is only good for business purpose and not so good for Gamers and multimedia use.
Thanks
-Previous comments-
HTC viva is a good business phone. It is sleek with touch screen in around 10K budget. Wifi features is there. The earphone is also of good quality.
However, if one is looking it for multimedia usage then better go for some other phone. Those who had experience with Nokia or similar phone with one key press for SMS, Phone, Photo, Songs will not like it. The user interface is not very easy and intuitive.
Also you wont be getting games, widget, utilities as easily as you would get it for other simbian phones.
Overall: As per my experience with this, it has some good business phone features but try avoiding if you want it to use it as multimedia phones.