Why do people care so much about things like this? The P25 is just another way for WWE to further their on-screen storylines and 'push' certain stars by ranking them at the top of the ranking. It's not a life or death chart is it. Get over it.
Anyway, who else would be #1? Cena has the bst win/loss record in WWE currently and has been performed well week in/week out for a long time now (whether you like it or not). He has only lost to HBK on Raw in recent months and has had more matches than most, so he will be at #1.
Who do you suggest to be at #1? Undertaker? Lost the title. Edge? Won the title, but was sneaky and hasn't been on too much of a roll recently (although he beat Kennedy and Orton). Lashley? Hardly done anything and lost the title. There's nobody who should be #1 but Cena.
But yehh, it doesn't matter anyway. It's rigged.