It's probably safe to say e-newsletters (and many types of e-mail marketing) are in danger of becoming useless due to spam and inbox clutter. Many of my ClickZ colleagues have written plenty about why RSS makes sense as a way of cutting through the clutter. I agree but am beginning to think perhaps the focus on RSS is more a symptom than a cause. The move to RSS (and other faster communications, such as IM) may be indicative of a larger trend that will affect how we communicate. [ClickZ]