Droid Charge Launch Postponed as LTE Outage Passes 24 Hours
In addition, Verizon has previously said that LTE devices would switch to CDMA mode if they were in an area with no LTE coverage. In this case, HTC Thunderbolt users (the only handhelds currently on Verizon's network supporting LTE) are seeing 1X mode, not 3G, Verizon has admitted in a later Tweet.
Verizon's LTE network is nascent, and thus an issue like this should not be unexpected. The 1X data mode is probably unexpected, however. AT&T's LTE network won't enter testing until mid-2011.
Verizon says it has "determined the cause of 4G LTE issue & are working with major vendors to restore connections," but that post was more than 17 hours ago. In addition, the the launch of the Samsung Droid Charge, Verizon's second LTE handset, has been postponed due to the outage.
Update: shortly after 8AM PST, Verizon Tweeted that LTE is back. Testing showed that it is, but you may have to power-cycle the radio.