Hi again!
Okay. I've read all the answers and want to make a small summary for myself (IMHO):
1) The MOST important: I think Wikipedia's markup complexity problems are not the problems of Wikitext idea. I think WP should concentrate on improving WP-specific markup (tons of various infoboxes and etc), maybe move some templates to extensions, instead of changing the wikitext totally or even worse - hiding it from the user.
2) I still beg MW developers to not throw the wikitext idea away! (maybe if it will prove being useless for ALL (100%) users one day - but I'm sure this day won't come). Visual editor itself won't harm anything, I will support it. But I'll say my users: if you want to make small changes, here is the visual editor. If you want to write something big, here is the plaintext.
3) I see there are usability talks. Improving usability is good, but targetting at people who don't want to be "technically proficient" (emphasis: DON'T WANT TO BE, not just "ARE NOT") and just want to press a magic button and "that's all" is not good. There are topics like "internal vs external links, users tend to find one and ignore other" - that's ridiculous, that's NOT the usability problem. I.e. I think we shouldn't think of "usability initiatives" as of 100% correct ideas.