I liked Geni the most. Second best was MyHeritage. Geni has a very beautiful and wonderful user interface.
I found all the following tasks were very easy and quick:
1. Registration & Login – Just Name & Email ID
2. Adding Family Members Is Easily & Enjoyable
3. Invite Members As You Add Them
4. Add Their Date Of BIrth, Added To Events
5. Tree Is Created With Different Views
6. View Map According To Date Of Birth Of Members
7. Intelligent Photos – Event Linker
8. Add Videos
According to Geni & TechCrunch:
Geni is the fast, free, fun way to create your family tree with your relatives and stay in touch. Free unlimited photo and video sharing. It is a social-networking website for families to explore their geneology. Geni aspires to create a family tree of the whole world.
MyHeritage is also a good site. It has nice features and various reports. You can also import GEDCOM data here. The most unique feature is MyHeritage Find The Celebrity In You Feature. Just upload your photograph and find the celebrity with which your face matches. You can also create a celebrity collage, morph celebrity images, look-alike meter. Try those tools. They are fun!
My vote is for Geni. Try MyHeritage for Celebrity Fun!