It is official. Germany is sending 14 Leopard 2 tanks to Ukraine. And has greenlit exports from other countries. The plan is to assemble at least two battalions of Leopards (~100 tanks) between Germany and other European partners. Poland has explicitly said it will supply at least 14 Leopard 2s. Germany says it may send more in the future. Several European countries have Leopard tanks available to export.
The US is expected to send 31 Abrams tanks and their support vehicles.
Don't expect the Abrams to see the battlefield for quite awhile though. The big question is if the Leopard 2s will be ready in time for any potential spring offensive. But both of these moves are significant political steps in this conflict.