No, I almost never use wifi.
There's a thread around here somewhere about the new antennas and being able to use 3G & voice at the same time. So far, the Thunderbolt is the only Verizon phone that will do this.
You are correct sir. The chip (exclusive to the Tbolt for the near future) uses SVDO technology. It seems kinda funny that they didn't put it on a phone that is 3G only, as it would be more useful on that device.
I even remember reading a review where the reviewer wondered why they didn't also put this on the Verizon ip4 so at&t wouldn't have any ammunition against them in their ads. The old ads used to say their
phones could talk & surf at the same time. The new ads (after the Tbolt) say their
iphone can talk & surf at the same time.
The ability to talk & surf while connected to wi-fi has always been there, because the phones would be using 2 different radios for voice & data (3G & wi-fi). LTE equipped phones can talk & surf because they also use 2 radios for voice & data (3G & 4G).
SVDO (Simultaneous Voice & Data) also makes use of 2 radios, but in a way that was previously not available on Verizon's network. Basically, it moves voice down to 1Rx (2G), & data stays on EVDO (3G).
The next evolution coming is found on the LG Revolution, which will be capable of voice & data on LTE, called VoLTE or voice over LTE, which uses a single radio (4G LTE). After a demonstration at MWC 2011, they mentioned possibly making VoLTE available in 2012.
Verizon also has stated recently that by 2013-14, all phones released on their network will be 4G. The plus side of that no more minute plans, you simply buy a data plan. The downside is with Verizon set to introduce tiered data this summer, your voice minutes will be coming out of your data plan.
Now, if the amount of data consumed by VoLTE is negligible, everything should be okay. If it is a noticable amount, along with texting & other services that currently aren't data, a person could find themselves looking at overages. Verizon has said recently they will charge for data overages under the coming tiered data plans, not throttle speeds as some have specualted.
Could be good or bad, but without details we can only speculate. If they do actually make VoLTE available in 2012, I'll be watching LG Revolution owners to see how it works for them before I make any judgement.