Better diagnostics when starting ndb nodes?
You can view what is going on with ndb_mgm -e 'N report eventlog' where N is the data node's nodeid. This won't necessarily give you an estimate of when it will be finished but it can be used to verify that stuff is indeed going on and that the ndbd isn't just spinning indefinitely.

ndb_mgm -e 'all status' is also useful, as it will show you the current phase your data nodes are in. You can read more about phases in Summary of NDB Cluster Start Phases in the MySQL 5.5 Reference Manual.