I was waiting for a long time for a feature like Priority Inbox to come, but one of its main downsides is that it is not available on Gmail's mobile version yet. I thought about it a little, and found a simple partial solution to this problem.
The nice thing about Priority Inbox is that it's based on labels (like many things in Gmail) — your important emails are tagged with the "Important" label. Therefore if you want to access them from your mobile, you just need to search for "label:important in:inbox" (or: "label:^im in:inbox"). Of course it's not a full solution, but it's something until full support is released.
Those of you who use Gmail's mobile web version can just use the following link to access your important emails: