Is there an alternative to the blog tour?

At KT Literary:

If you’re an avid reader of a certain blog, does a guest post by an author make you check them out, or do you skip them, to hear more from the bloggers you came to the site to read? Or do you skip the sites that host blog tours regularly almost completely? What’s the middle ground? To reiterate Jenn’s question, is it all just noise?

Answers from my perspective:

• I almost always skip blog tour posts...
• ...which means that I generally don't read blogs that host a lot of blog tours.
• I do enjoy blogger-run blog tours like the Summer Blast Blog Tour: as each post focuses on a different author, the content is consistently fresh, and I don't feel like anyone is trying to sell me something. Blog tours like that are great for readers, but as the author/publishers have no control over the whens or whos or wheres, they don't really work as marketing tools.
• While they're almost always 'noise' to me, blog tours must work on some readers, right? Otherwise, no one would bother with them. Or is it the giveaways that drive the traffic?

Thoughts?