I like that they're bringing back 50:50. That lifeline forces a contestant to ponder a question carefully before walking away or going for it and winning money or dropping down to the last safe haven. I won't miss the retirement of Jump the Question; contestants could forfeit some significant money from their personal bank (one taping I saw last year featured a contestant jumping what turned out to be the $25,000 question).
As for the money tree itself, I wish there were 15 questions, per tradition, and that the money amounts double, rather than increase by increments ($500, $1,000, $2,000, $3,000, $10,000, $50,000, $100,000, and $500,000). Having the "double" aspect of the previous money tree helped elevate the tension and risk that was associated with the game. But I'll take the return of the money tree in any form.
I'm optimistic about the changes this season. I might catch a taping or two in Stamford, when I get the opportunity, but I wonder if this will be enough to get viewers back to the show (hopefully we'll finally see a Millionaire crowned this year).