There are essentially two camps on the Labor Theory of Value.
Labor has intrinsic value that can be codified by some system in place to do so.
Or.
The fruits of ones labor should be dictated by the laborer.
The former camp is capitalistic, the latter camp is socialistic.
While capitalism has ventured into the subjective theory of value, labor still does have "intrinsic value" that can be "codified." Minimum wages, market rates for a given specialty, and so on. The labor theory of value therefore in a capitalist system is still alive and quite well. My job on a daily basis can be seen as "digging a hole in the ground as worth" even if that hole serves no purpose. For example, I spent an entire summer quite literally throwing cement into a truck, by hand. We had access to machinery that could've rendered this job meaningless in a matter of a week at most, but we opted not to use it, simply on the basis that if we got the job done in a short period of time, there would be other jobs (potentially harder) that we would have to do, and the cost of renting the machinery was to be taken into account. Of course, I work for the government so this is particularly common, and I don't really have an issue with it.
Socialism, actual socialism, does not codify the value of labor, but it recognizes that that value exists simply because the laborer is the forbearer of it. You can see this labor more explicitly in the act of one person acting for themselves to achieve some goal, such as taking out the garbage, or vacuuming their home. There is value expressed in those behaviors (the value of not living in filth, the value of having clean flooring, etc). When it comes to more collective tasks, such as several people working together to build something, that labor is expressed differently. Socialistically speaking all who work on a given thing logically would benefit equally from their contributions, even if in the end ones contributions are hardly significant. So say I'm welding together parts to make a roadster, so I help those working on their own roadster to achieve the same for them.
This is where things get tricky. You can help me build my roadster, but I have an idea, I use my roadster to achieve some other economic activity, such as using it to traffic drugs from one town to another, and I pay you to complete your own roadster. To be able to determine the worth of my labor we must then go back to the codified systems that say what it is worth, the markets. But then we're back to capitalism, aren't we? There's no substantiative difference between me paying you to build your roadster in either situation, except that actual socialism would recognize my labor regardless, whereas the capitalist approach would recognize only the labor that I contribute as the system defines. I might be a poor welder, and you might have been doing most of the work, but we both built the roadster.
Let's look at it another way, in socialism that is actually practiced every day, and part in parcel to the very means of communication you are using to write on these very forums. For instance, this website is running Linux (according to netcraft), an operating system made by tens of thousands of people, contributing their labor, which has value, and asking for no monetary recompense in return. This is the latter camp of LTV, because those who write the code are deciding what it is worth to them. For them the worth is not necessarily monetary (though contributions to Linux may come from people who work for companies that have monetary goals), it is social.
Eben Moglen makes the case much more eloquently than me:
http://en.wikisource.org/wiki/Author:Eben_MoglenAs it stands now no state is actually practicing LTV in a socialistic sense. It is intrinsically capitalist.