Does a seam ripper get dull/blunt? Lately, when I use mine, it seems like it's more difficult to remove stitches.

Sure it does, just like any other blade ~ it will get dull and need to be replaced.

I think mine needs to be replaced more than normal because I use it so much. :-) :-) :-)

Yes, and the chance of actually ripping into your fabric increases. Ask me how I know.

I am having a very loving relationship with mine (all of them). When I sew I make sure there is one in hand, because I know I will need it. I keep several, because when one needs to be replaced, there is another one.

Yes they definitely do get dull, and mine are at the point right now lol. I use mine more than others as well. Especially when I try to do "sleepy sewing" NOT a good idea ;)

Guess I need to replace mine, since I probably wore out it taking apart about 80 half triangles sewn together!

this is so true, and it depends on how much you use it.

I just bought a couple more, as mine were dull. Wish I could sharpen them!

The wonderful owner of my LQS told me that the one thing quilting ladies/gentlemen never replace are their seam rippers and it should be the one gift they treat themselves to.....

I get a new one about ever 6 months (I rip a lot LOL)