A few things to come in the future in my opinion, sooner or later:

• income tax paid to your national government on virtual earned revenues,
• more CAD tools like now this exporter named Henshin (AutoCAD to SL),
• strict enforcing of this adult flag,
• a 3rd party API to extend the client with plugins like importers, adding client side scripts etc.,
• saving contents with LSL to notecards,
• some sort of external backup,
• regulation of the Linden Dollars, perhaps by the Fed, if it becomes popular enough,
• some kind of interests on credits, defined by whomever,
• more law rushing into SL (it has never been out of SL),
• some kind of external grid/corporate grid, well new grids anyway,
• the sale or IPO of Lindenlabs,
• some bridge to existing instant messaging networks like ICQ, MSN or Jabber.