> if you're worried about the information Google collects on you and so choose to plaster that all over message boards every time Google is mentioned - exactly what are you accomplishing?
If you're worried about the information Google collects about /everybody/, and you're posting in /relevant topics/, I think you're accomplishing quite a lot. I think it's really important that when new technology is announced, interested parties discuss both "here are some exciting new possibilities" and "here are some areas for concern". In an impartial discussion forum, a product announcement shouldn't just be an excitement-fest.
> Do you think the people reading your comment don't already know what information Google has available?
This technology will likely result in Google and others collecting and having access to new sources of information about people. I think that many people reading the announcement might not immediately think about some of these implications, and I think it's a great time for review and examination of the topic.
> Do you think Google's going to change its practices because you complain?
I think some engineers and others working on this project and other projects at Google probably read HN, and I think comments here could have an effect on how they build this product and what data is eventually sent to the company. Reading these concerns might be a good reminder to reflect on these things from time to time as well.
> I think the grandparent's point is to focus on things that are actionable.
Action without reflection is a dangerous formula. Google is taking action by building this and announcing it. What we do at HN is learn, reflect, and discuss.