Other Fixes:
Unicode love:
??Various Unicode character input fixes for Unity GUI.
? Standalone Windows games can launch from Unicode paths or when Project Name contains Unicode characters.
??Fixed Paste with some Unicode strings not working.
??Fixed Font.HasCharacter() for some characters.?
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Seeking in compressed audio (with .time) now works and with a much better precision.

Animation fixes:
? Fixed Animation.Sample() not working if animation was not playing before.
? Fixed Animation.CrossFade and Stop not clearing out queued animations.
? Fixed Animation.IsPlaying for queued animations.
Fixed Application.loadedLevel being initially -1 in players.
Fixed Mesh.tangents producing null reference exception if mesh had no normals nor tangents.
Fixed EventType.ScrollWheel delta values being about 100x too large on Windows compared to OS X (now they match OS X).
Fixed copying text into clipboard producing extra ASCII zero character at the end on OS X.
Fix unrecognized keys (like volume up/down on some keyboards) triggeting unrelated input axes on Windows.
Fixed Mathf.Ceil and Mathf.CeilToInt returning next integer number if the argument was integer already. D'oh!
Fixed audio playback from streamed Ogg files.
Fixed crash when streamed video download is cancelled.
Fixed terrain tree colliders for terrains that aren't placed at zero.
Fixed MovieTexture playback issue.

Upgrade Guide
Unity 2.5 projects are compatible with Unity 2.1, so if you do not use new 2.5 features, you can open your projects with Unity 2.1.

Timeline window for creating animations directly in Unity was removed in 2.5. Of course you can still author animations in a 3D application. This feature will return even better in Unity 2.6 including High-end Curve Editing and support for animating any property including material animation.

Some of the Editor scripting API was refactored, here are the largest changes:
EditorWindow.OnCloseWindow is removed. Use OnDestroy instead.
Hotkey part in MenuItem name requires a space character before the hotkey now.
Removed Mac Ctrl (^) modifier support from MenuItem hotkey.

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