Yes, the report is very clear that by early voting they mean absentee voting and in person early voting. About 82% of early votes are absentee and 18% early voting in 2010. A very similar percent is reported for 2008 from Cleveland (the only county I can find a breakdown for 2008)
United States Elections Project
Slightly over 5.7 million people voted in Ohio in 2008. 29.7% voted early which is 1.7 early votes. Of that about 18% are walk in early votes...or about 306,000. As you can see from the tables on pages 18 to 20 the early voters were Democratic voters by 5 to 10% higher than those voting on election day. That is a huge difference.

I do appreciate the fact that you took the time to read the link and consider its contents. We need more of that around here