I have never edited a Wikipedia article myself, and have no vested interested in this debate one way or the other. That said, in general I find Wikipedia incredibly useful on a day-to-day basis; I probably check it for a minor point of information every few days, such as 'what are the light requirements for growing clematis?' For most of the information it covers, I've found it tremendously helpful. Given that helpfulness, as a user, I'm more than willing to put up with a certain amount of delay when potentially controversial facts are being verified by multiple edited sources. I'm not particularly worried if they currently privilege print sources; I doubt that will last long at all, as more and more professional publications move to electronic publishing. The key is that the source be a reputable publication, and has been through some sort of editing process. It doesn't seem so much to ask.
I don't have the time/energy/patience/attention-to-detail myself to be a Wikipedia editor, but I'm very grateful to those who do the work. I'm sure the process will continue to improve over time -- the encyclopedia itself improves measurably in depth and usefulness every month. I find that impressive.
Re: approved sources -- I don't know whether Wikipedia already does this. But it seems like it would make the volunteer editors' lives easier if somewhere behind the scenes (but easily accessible to editors/users) they maintained a list of pre-approved sources, both print and electronic, by subject area. This might cover print publications, electronic publications, recognized experts in the field and their blogs, etc. So that if I wanted to make an edit, I could quickly glance over that list to see if I could credit a trusted source -- I think I'd be personally much more likely to go to the effort of making an edit if I knew that the source I used was acceptable, and my edit wouldn't simply be reversed immediately.
The process for making it onto that list should also be fairly simple -- perhaps as simple as having a few representatives from already-vetted publications vouch for your expertise. So that, for example, Charlie Brown who edits Locus (or one of his representatives, such as Tim Pratt), could vouch for 'Making Light' as a publication from industry experts. Eventually, that might even lead to my personal blog being listed as an expert source, given my years of professional experience as editor and publisher, and then when editing Wikipedia, I could just cite my own blog. That would simplify matters enormously for me. :-) Though it does seem a bit circular.
I couldn't resist linking to this comic, from XKCD: