The Linear Tape Open Consortium has announced two more LTO tape generations, taking capacity up to 32TB compressed with LTO-8. It has achieved this with an increased compression history buffer. It says that testing shows this can improve compression rates from the existing 2:1 to 2.5:1. Consequently raw tape capacities grow less …
With the LTO 8 tapes it'll only take three days to backup my pron collection.
If you were serious you'd get yourself a tape library with multiple drives, you can cut that down to about 12 hours : -)
Plus you can make the autochanger robots fight!
Seriously, if you have less than 2TB of data (about what tapes can manage nowadays), you'd be better off just dumping that data to an HDD. Better rewrite sustainability (for those 30-day tape cycles), and much longer archival lifespan. I wouldn't trust my data on a tape for longer than a few years. Unless those 32TB+ (compressed) tapes cost less than $100 (and I actually have that much data to dump in a full backup), I would still mark them is less-than-useful. Especially at $3k per device to write them.