Well, the Sonic's article is written for non-technical public, so it does not explicitly mention "packet writing" because no one would understand what it means. So while statements like "The built-in AuthorScript engine provides features within Windows Vista that help users archive digital memories to CDs and DVDs, create custom music discs, and perform important data backup functions." is pure marketing, the title of that article, which is "Sonic Provides Burning Engine in Windows Vista", says everything.
I do not use packet writing for permanent recordings to +/-R discs because it is inpractical to use it in this case. Normal session-based writing is more suitable here. It should also be faster, because from my understanding of how it works in case of packet writing the recording program has to constantly check what's going on on the disc during writing, while in case of session-based writing it just writes an "image" which it creates in its "head" prior to writing. So while packet writing is more sophisticated technique, its use for +/-R discs creates unnecessary overhead without giving any advantage.
But I also see it absolutely inpractical to use session based writing in cases where I use packet writing. Suppose you have a folder, say "My Documents" which constantly changes. I add, edit and delete files there every day. I would like to have a disc with the content of that folder for two purposes: 1) Just to keep another backup copy of files. 2) To be able to work with files on my home laptop. So, according to those who hates packet writing, should I re-backup the whole content of "My Documents" at the end of a working day just because I added one file, deleted another and changed yet another? Is this what you are suggesting to do? No way!
But my main point is that even if we assume that you are right that packet writing technology is more prone to sudden errors because of it's complexity, most problems (99.9%) which people experience with packet writing software currently on the market are not due to issues inherent to packet writing, but due to trivial bugs in software and development decisions made. It is not inherent packet writing problem, that Drag-To-Disc 9 causes "Blue Screen" every now and then, nor is the fact that it was made incompatible with discs created by previous versions. Or that Nero InCD was putting current dates for copied files in four consecutive versions of the software from the end of June to the end of November (they finally fixed this bug in Nero 126.96.36.199).
So if the implementation of packet writing in Vista proves to be good, the packet writing technology will finally wash away the stain of irreliability, which was put on it by negligent developers of current software.