I have learned that next year voting will be open worldwide, so I guess that means I'll be able to vote. I think it will be interesting to see what happens, but I'm hoping they will be upgrading their voting system to handle more votes, since I know already people have sometimes had problems with voting in the last couple of years.
Apparently you will need to use a credit card. Up until now, I didn't know people paid to vote.

And also they will be doing away with the juries for the semifinals. I know people complained a lot about some of the more fun and creative songs and performances not going through in favour of a lot of slow songs this year, so I think people will probably be happy about that. At least, based on comments I've seen online.
 

Oh yeah, I had forgotten about that. That's a very good point.

I have wondered those same questions, when it comes to how it could affect the results. It will be interesting to see if information is made available after the contest to see how different countries within the "rest of the world" section voted. I think "Snap" from this year, which ended up very popular worldwide post-Eurovision (I heard it on the radio at the grocery store a couple of weeks ago! The only other Eurovision song I've ever heard at the grocery store is "Arcade," which also got popular worldwide, though I like "Snap" better) could have possibly done better if other countries voted. I thought it sounded a lot like other songs that have been popular in North America, though I didn't think the stage performance was that interesting even if the song is pleasant to listen to. I can only assume people will still respond to the performance elements as well as the musical ones. Something really fun or eye-catching can't be ignored no matter where you are from. I think people in North America and other countries also have diverse tastes within populations, even if there are certain big trends. (e.g. people who listen to classic rock or 70s punk music even if they didn't grow up when that music was released, even if other styles of music are popular among their friends). All kinds of things can impact taste! I suppose that's stating the obvious, and a long-winded way of saying I don't know what will happen but I'm curious to see.

Watching a rehearsal sounds like it could be fun! It would probably be a late night to attend the actual televised performances (I've had to remind myself a couple of times that Eurovision is an evening broadcast, since with the time difference it's always live in the afternoon here -- this year I have a job that will probably prevent me from watching the semifinals live).