I listen to a LOT of music on my phone. I bought a 16GB card from Costco for $21 and that seemed to help the skipping a bit, the 2.3.4 update helped it even more. I say helped because I still get a few skips here and there. I came to VZW from T-Mobile on a Mytouch 4G and it had music skipping issues too, about as much as I see on my X2. It's now occasional and only when I use a wired headset (my stereo BT headset doesn't skip).
On a 3 hour road trip last week I only counted 3 music skips down and back (6 hours of drive time with a wired connection to my stereo). That's on par with what I saw with the MT4G and other Android phones I had on T-Mobile. Before the update it was much worse and much more noticeable. On the same trip I had dozens of skips before I got the update (everytime an e-mail, text, or IM came it my phone would skip).
So I would say that if you are having more skips then seek a replacement phone.
I have the default Memory card (8 GB) that the phone came with. Do you think that music skips are because of that? By the way, the memory card's access speed is very slow. That is, whenever I transfer media, like Music or Movies from my Computer onto my Motorola's external SD card it transfers at best at 1-2 MBps... Which is very slow, in my opinion. So, in light of this, is my music skipping due to the memory card. If so can I get it replaced or what SD card do you suggest me to buy?