It's not exactly "lots", onefineday. And it's limited to people active on Twitter.
But speaking of active, if iRiver wants to create some momentum with this blog, it needs to actually post stuff. Development plans, articles covering those bits missing from the "manual", tips and hints on how to make formats like PDF and DOC and TXT work on the Story, downloadable public domain books formatted for optimal use on the Story (I'm guessing that means ePub only) ... these things would create some loyalty and sense of support for existing users and prospective purchasers.
Since iRiver doesn't have any customer support to speak of (trackable incidents and follow-up on issues, for instance), then a support forum on the blog with FAQs would go a long way to helping existing customers feel they hadn't bought abandonware.
As it is, the blog seems like a sales pitch only. That's not a blog, that's junk mail.