Google's forays into the TV advertising space will raise some new questions about the company, and I think the biggest one is what it must ask of itself: what is Google's value proposition for its constituents? Here are some of the many candidates:
Relevance/Targeting: Advertisers reach targeted consumers. Consumers only see the relevant ads. This also ties into other selling points like efficiency.
Speed: Advertisers quickly plan campaigns. Publishers quickly integrate Google into their sites (AdSense, Custom Search Engines, Gadgets, etc). Consumers find info quickly however they want it - google.com, toolbar, personalized homepages, etc.
Reach/Comprehensiveness: Advertisers can reach just about every consumer they want to in given markets. Consumers feel that Google has everything in its index, from the spidered sites to paying advertisers.
Ease: It's easy to launch a campaign with Google. It's easy to search there. It doesn't matter if other services are better.
Cost: For advertisers, it's economically efficient. Publishers get the rev share that works for them. Consumers enjoy all the free services.
Measurability: Advertisers can clearly measure the ROI and ROAS of their campaigns. Publishers can use Google Analytics to measure site traffic and visitor conversions. Increasingly we'll see ways to tie online activity to offline events.
All of these play a role, some more than others, and I'm not coming up with any grand answer here. There are other factors not listed too. If it's all about relevance, BusinessWeek says Google can't win there with brokering TV ads. Yet if there's more to Google's value, such as the ease of brokering a multi-channel campaign through a single interface, potentially consolidating the agencies marketers work with as well, then the value proposition is something much greater.