An offline wikitravel would be incredibly useful for travelers. I haven't found this yet so I built an offline wikitravel for android:
https://market.android.com/details?id=com.heliod.eutravelgui...
You can stick both wikipedia and wiktionary on it. Quite possibly also Wikitravel, if they provide dumps.
http://wrmlbeta.s3.amazonaws.com/entrav-20111105.7z.001
In the age of nearly unlimited connectivity, I still find my Wikireader an invaluable device when traveling.
But you're right, waiting forward for the offline HTML5 Wikitravel app. Now with antimatter15's script it's only a matter of time and goodwill :)