Writely has started accepting new accounts
In any case, Writely seems to be well done, although it did throw an error during one operation. I expect that it will soon be excellent. I have become rather addicted to Latex recently - even more so than in the past, and with a handy subversion server, web based word processors are less of a draw to me because it takes a few seconds to grab working document files. That said, web applications like GMail, flicker, Picasa Web Photo site, Netflix (excellent!) and others take up almost all of my non-working time with computers.