If I take DDO as a comparison, there is so little solo content, that you have to group. That per se isn't a problem, the integrated tool works pretty well, although even there one finds LFG in the chat channels. Problem in DDO is, that while you are searching, or don't feel like grouping (by choice or by circumstances) there is not much for you to do in this specific game :( At least in e.g. you could do other things, like crafting.
(very vell described in a massively article a couple or so months back).

Re - InfamousBrad: there is in most MMOs a ShareQuest function. Works though o/c only if it is not chainquest.