I wouldn't expect much in the way of improvements (read additional functionality) because of the acquisition. Google is a company for the masses, Trimble is sector and market specific. The only changes I would expect for a while are integrations with Trimble's current software and hardware.
Sketchup is a market specific product in the same way that Google App Engine is. I strongly suspect that Trimble's products already interface with Sketchup either directly or through standard ESRI or Autodesk file formats.
