Absolutely yes. Though it's not really surprising with how bug-riddled Brotherhood and Revelations were - still are, in fact. Ubisoft are terrible for pushing out games before they're polished nowadays.
Yes, and anyone who yes Y Skyrim, that game hasn't been out a while? It's been a year O.o
Lots of bugs and glitches, disappointing as hell. A lot of it has to do with graphical things, like icons not appearing (Frontier general store icons not appearing until you actually touch the ****ing door, liberation mission icons missing). Hell, the icon for the Benedict Arnold DLC has not appeared for me at all (finished the game, about 99% sync now), what a ****ing waste of £5 that's been.
Also things like Common Man book glitch, even if you manage to scan everyone you might get the 2/3 woodworkers glitch which might prevent completionist.
Finally, just things like you're close to your custom marker and you're going away, suddenly "WARNING: Moving further from your target will cause desynchronization", and sometimes it actually starts happening, err WTF. Also not a bug, but seriously? "WARNING: Your ancestor skinned every animal they killed. You will desync if you do not skin the next animal you kill".