Re Lifetime: Good point, this is value (or more precisely, revenue) to date.
Re Value: The post outlines the first step in deriving "true" value. The intent is to allow you to take the ltv as described & subtract the appropriate costs to find a net gain or loss.
Sorry for not being as thorough as I should have, I'll try to get an amendment from Paul.
Here's an example to help illustrate:
Discounted (future) revenues: $100
Discounted (future) ongoing costs: $20
Value: $80 ($100 - $20)
Acquisition cost: $60 (e.g. adwords)
Net Present Value (NPV): $20 ($80 - $60)
Note that revenue to date did not figure into any of the above - we're concerned with the future here, so the past is only useful in as much as it helps you with forecasting.
The wikipedia page on CLV is surprisingly good, have a look.