I don't see anything too obvious on my own system, but that's not terribly surprising. Because most debian-based distributions are updated on a regular basis, and because mepis tracks the testing/unstable packages lists, any attempt to place a version number would be feeble, once the system is up and running, and being updated on a regular basis. This, for the most part, is the way many Linux systems are headed, as it's better for users to have an up-to-date system, than lock them into a certain version. Of course, it's better for most commercial versions to try and push the upgrade cycle (how many people buy "newer better" for no better reason than it's "the new version"?), but even there, many are migrating towards a subscription model, which offers similar benefits and a more stable income.
(Personally, I think subscriptions benefit the consumer in one potential way, because if a company notices that less people are renewing their subscription, they may react quicker and more decisively to correct their problems, than if they only notice a problem every couple years. After all, look at how MS is panicking with their less than stellar subscription efforts. Without the subscription model, they would've had to wait another year or two before they realized users were migrating away in the numbers that they are.)
As a result, while a version number might be useful on a superficial level, it's more important to have a system that's been updated on a regular basis. Also, it's more helpful while troubleshooting to say "The system was completely updated last Saturday", than to say, "Mepis 3.x.x" which might mean anything up to several months worth of potential problems.
Hope that explains it a little.
