I have a site with over 10k original quality pages. it consists of 30+ sections. now we have worked on preparing several new sections for the site. they are almost ready now. the question: shall we put entire sections online and start promoting them straight away or put just a bit, start promotion and upload parts of the sections within certain period of time? the new sections are pretty big. they may be as much as 15-20% of the existing site all together. so put all now or put parts (main pages of each section) and wait?
My opinion will be to put about 30-40% now and then add content every day. It will give a fresh look to your visitors and you will have more people returning to your site on a regular basis.