Philipp Lenssen at Google Blogoscoped observes  that Google could potentially use OCR (optical character recognition) to attempt to derive text from signage and such within Google Street View images in order to create further enhancements.
Grauman’s Chinese Theatre in Street View, Los Angeles.
However, I see a much more immediately valuable use that could be put to text scanned from the images — quality improvement of address pinpointing functionality.
I’ve written before about a number of the causes of errors in maps , and one of the most frequent errors is in how addresses get incorrectly pinpointed down streets. If Google Street View images were scanned for text as Philipp describes, address numbers for businesses and residences could be much more accurately associated with locations.
Street View could be used to improve mapping quality in many areas.