Does Flickr regret dropping a vowel in its name? There have been lots of naming trends and they don't seem to have had much effect on long-term success. What's wrong with -ly?
It's not a bad thing at all. Flickr works because it is still pronounced Flicker. Personally anything with -ly irks me the wrong way and it feels like a branding cop-out at times. Just imagine if Google was called Searchly or if Basecamp was named Managely. From a branding perspective in 5-10 years time adding -ly will look dated. You'll think back to web 2.0 as if you were looking at a geocities page (or worse Homestead). Not to say this project should be aware of its branding at all.
I think the general case is that it might have been innovative for one name, but the rest sound derivative, unoriginal, repetitive, derivative, unoriginal and repetitive. And many abuse the Lybian TLD.