OpenComputers 1.4 is now available.
Even more important than usual, remember to make a backup of your world before updating. Seriously. Do it.
For downloads see Curse.
VERY IMPORTANT
You cannot downgrade to OC1.3, after loading your world in OC1.4, without losing converted blocks. To future-proof things, the way blocks are handled internally has been switched around a bit in 1.4. This means all of the old blocks have to be converted to the new format. For blocks that are in the world this happens automatically. For blocks in inventories, this also happens automatically if they are in a pla