I'm one of two minds.
I follow web marketing news as I've done for many years, even before my business card said "web marketing" on it. If I haven't mentioned it before, I used to say that I hated marketing. But my wife waded through that and corrected me. I really like marketing, but I hate being marketed to. And from that, I've become adept at noticing when I'm being marketing to aggressively and when the methods used overstep certain privacy walls I like to keep intact. I also feel this improves my abilities as a marketer and my moral compass that guides me towards doing it correctly.
That's why seeing an article like the following one gives me two separate and distinct feelings. First check out this Ars Technica piece on how Gmail has changed one aspect of how images in email are used.
Ever wonder why most e-mail clients hide images by default? The reason for the "display images" button is because images in an e-mail must be loaded from a third-party server. For promotional e-mails and spam, usually this server is operated by the entity that sent the e-mail. So when you load these images, you aren't just receiving an image—you're also sending a ton of data about yourself to the e-mail marketer.
But Gmail has made this irrelevant. They are caching all images on their own servers now. They will download all emailed images, which triggers the marketing software to indicate the email has been opened (when perhaps it has not) and then obfuscating the actual user's information. Gmail has essentially put themselves been their user and the email marketer.
On the one hand, I'm excited about this because as a Gmail user, it means my personal information is a little better protected from anyone marketing to me or researching me. On the OTHER hand, I work in email marketing and this is going to potentially change how we measure who has opened our emails and how many of them successfully read them.
As an aside, it could be argued that Google is doing this in Gmail not JUST for user privacy protection, but so they can surreptitiously learn all of the information from those images themselves... and perhaps turn around and sell that information to their AdWords users. But it's likely they could already have been doing that previously.