Only one song from Denmark to Norway didn't end up in the top 10 - and 4 of the bottom 5 were in the first 5 songs. So going up early is a no no. I think Moldova (the only one of the first 5 not to end up in the bottom 5) could have done a lot better if she was on later.
It's also quite similar to 2009 in that the last two songs to perform both underperformed in the results. So you want to be on late, but not too late (17th-24th are normally the best slots so that fits, although songs that do well are normally more evenly spaced) - and if you're in the middle, going just before that seems to get you a good result. [/geekstats]
I guess by Norway, people had made up their mind about what to vote for and the last two songs suffered. But Ireland flopping so badly after going on last is unusual, in the last 10 years, the song performing last has ended up in the top half 7 times, 3 of those in the top 5.