When doing a forge update in forge 1.2, it prompts (and then if you're in windows auto selects the upgrade) for 2.0 Alpha2.

[no project] john.ament $ forge update
forge update
**INFO** This Forge installation will be updated to 2.0.0.Alpha2
? Is that ok ? [Y/n]

Update in progress. Please wait... \

which is then followed by:

C:\Users\john.ament>forge
Error: Could not find or load main class C:\forge\forge-distribution-1.2.0.Final\forge-distribution-1.2.0.Final\lib\addon-manager-impl-2.0.0.Alpha2.jar