VtechTaka: I have had very mixed results mixing and matching basebands with kernels it seems to me there is some correlation between the 2 in regards to radio stability ,you may be able to interchange from a compatibilty level but it doesnt always translate into a well matched symmetry from my experience at least.
I can say with absolute certainty that there's no tie between a kernel and a baseband.
Samsung have released 4 sets of source code for the GT-I9100. There was an original release and 3 updates. Almost all of the custom kernels available are built from one of these 4 sets of source code. A small number might be built from the CyanogenMod source code, but these are fairly rare in comparison.
There are no such sources for baseband packages. The only basebands available are the ones from Samsung. (This is true even with CyanogenMod, as they use the Samsung basebands with their code.) Samsung have released a large number of basebands, as they keep tweaking things to try and get a good mix of signal strength and battery life. They're also customised for certain carriers, such as Vodafone or Telecom.
So, given that there are only 4 major firmware sources (main release + 3 updates), and dozens of basebands, there is no possible way that a baseband has any tie in to a kernel.
Also, I've been following custom kernels for around 8 months or so, and have never seen any mention of a kernel dev writing specific code to target a specific baseband. If there was any matching between baseband and kernel, the devs would comment on it so that people would use the right baseband.
Edwood: I have been searching for a couple of days, and not finding. I am looking for a changelog or 'highlights' or any information at all about the firmware update I just performed using KIES.
Strangely, Samsung never release any changelogs for their firmware updates. They simply make new firmware available and expect that people will update.
The only good news is that they go through a fairly extensive testing process, especially for carrier-branded variants, so any update is going to be an "upgrade" of some sort.
For example, you might find that the VFNZ update will contain a newer version of the base Android 2.3.x OS. There is a known set of changes that are included in each of these versions.
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