For those of you wondering what has changed in firmware 3.4. Here is what curtsy of marcans wiimpersonator.
Twilight hack 0.1b1 gets removed.
Patchmii IOS gets removed
Custom channels also GET REMOVED.
====== Titles Added ======
Title ID: 00000001-00000032
Contents: 15 (of which 14 are shared)
Title ID: 00000001-000000fe
Version: 0x 2
Contents: 1 (of which 0 are shared)
DO NOT UPDATE UNTIL MORE IS KNOWN.
"We may without notifying you, download updates, patches, upgrades and similar software to your Wii Console and may disable unauthorized or illegal software placed on your Wii Console to ensure that your Wii Console is operating properly and efficiently, comply with applicable laws, assist law enforcement, protect us and our customers, or prevent the use and distribution of software obtained through improper channels." (editor's emphasis)
Check out the full report on exactly what has been changed here: