If you pay attention to your daily security run emails on your DragonFly system, you may see entries like this:
+nlookup() at nlookup+0x623 0xffffffff806eff13
+kern_rmdir() at kern_rmdir+0x25 0xffffffff80706db5
+sys_rmdir() at sys_rmdir+0x4c 0xffffffff80706f0c
+syscall2() at syscall2+0x11e 0xffffffff80bd9f9e
I see it on the machine where I run this Digest, as the caching mechanism adds and deletes files rapidly.  Matthew Dillon has placed it behind a sysctl, so your messages log will be a little less noisy by default.
If you are trying to use both NAT and IPv6 with pf on DragonFly, there was a bug (seen here with FreeBSD) with :0 where it would use link-local addresses.  It's now fixed.
If you are using 'set skip on ...' in your pf config, it used to match any interface that matched the specified type.  It now only matches members of that named group.  That may change behavior of your pf rules; check the commit to see what to look for.
It's apparently possible to get a panic by yanking a HAMMER2 disk out of your system, which is only likely when using a USB thumb drive, formatting it to HAMMER2, and not bothering to unmount it.  Anyway, that poorly-described-by-me problem is fixed.
There's an odd bug in ipfw that is now fixed in DragonFly 6.2/6.3.  If you are using ipfw and adding networks and hosts in a specific order, the netmask will be set wrong. There's also a problem with the overnight bulkfree cleanup in Hammer that's had various attempts to fix it over time - it's now really truly fixed.  It mattered only if you had an extremely large number of inodes - 100000000 or so, Matthew Dillon wrote up an explanation for both.
I use date(1) just rarely enough that I can never remember the right arguments to create a human-readable result.  Now, there's an -I arg to date(1) that uses a word instead of a format string to get ISO8601 output.
It may be because I am a nerd but I enjoy reading detailed explanations of bugfixes like this one for HAMMER2.  This fix is present in the 6.2 release, of course.
I tagged DragonFly 6.2, and I'm planning for release later this week.  Release notes and ISO/IMGs to come with the release, as usual.
Tomohiro Kusumi has removed the old GNU implementation of ext2fs from DragonFly and added the non-GPL-encumbered FreeBSD implementation of ext2fs.