Recap: A while ago we discussed date conditional switching templates: http://lists.wikimedia.org/pipermail/wikien-l/2009-May/100714.html . The problem to be corrected was the use of future tense language which then becomes outdated and thus notably incorrect. This also has a greater effect of casual correction patterns which essentially annotate the error rather than fixing it. For example:
""Apple's iTunes store *will start* to sell DRM-free 256 kbit/s (up from 128 kbit/s) AAC encoded music from EMI for a premium price (this has since reverted to the standard price).""
A proper correction would have simply changed "will start [to sell]" to "began [to sell]" and that would be that. Time and tenses require a little bit of thinking however, and an editor made a parenthetical comment (edit note, annote) in place of a considered switch of tense. Forgivable but incorrect. If the {{dateswitch}} template idea was fully implemented and used, anyone writing future events could simply write {{dateswitch|will start|began|ON DATE}} and the switch would happen on the date.
The idea had some support, but people had some issues with dateswitch templates that would produce the wrong output because of some later change in the input. I guess that this might be more rare than common. The above example is notable however of where they miss the point. I note that we now have a category for some tags which relate to time, but I don't know about some of them: http://en.wikipedia.org/wiki/Category:Temporal_templates These appear to be largely template messages, and if we are to employ actual computational power in helping deal with outdating, would it make sense to make a distinction between temporal messages and temporal (functional) tags?
-SC