The heads-up is likely to be helpful, and may help you make a more informed decision before you sign up. However, many users (particularly those in the Unroll.me blog comments) see this as an insincere apology. Notice how he's upset about people being upset, not about the sale itself? That's what users are angry about -- that Unroll.me sold potentially revealing info to a company looking for a competitive advantage. While it wouldn't be trivial for the service to tear apart its business model, a direct acknowledgment of the real frustrations would have helped.

And as Daring Fireball observes, the statement raises questions about the degree of anonymity. If Unroll.me scrubbed billing info but not the routes people took, for example, that may have given Uber a roundabout way of identifying people (such as drivers serving both Uber and Lyft) based on trip locations. This doesn't mean that Uber had identifying info or misused it. Rather, the issue is that customers don't really know what's happening. No matter what Unroll.me says, its users simply have to trust that the service knows how to fully respect their privacy.