I heard through the grapevine that Sprint is currently negotiating a merger with Clearwire and, if successful, will rebrand themselves under the Clearwire name. Can anybody confirm this?

The merger details were announced last week.  This is for the WiMax (Xohm) portion of Sprint only.  If/when the merger is approved by the FCC, the Sprint Xohm employees will become Clearwire employees.  Sprint will own 51% of the new company, since they are contributing the most $$ via spectrum holdings.  Then Sprint will become a reseller of the Clearwire WiMax product when it's up and running.