If that sounds like a mouthful, it is. Here's a simple explanation: The Senate still sucks. Slightly longer: The Senate not only has to vote on whether to proceed to a debate on legislation, it has to vote on whether to vote to proceed. It has now done both. Given current Senate rules, the lopsided margin in favor of moving forward is certainly better than the alternative, but it doesn't guarantee final passage. Once the floor debate comes to an end, moving forward to a final vote on the legislation itself will once again require 60 votes ... because the Senate still sucks.
There's a parallel here with gun safety legislation, which also moved forward for debate despite being ultimately killed. However, the vote to move forward on gun safety legislation was narrower, with 68 senators voting in favor. Unlike immigration reform, some Democrats opposed the underlying legislation, making achieving the 60 votes needed for final passage an impossible task. This time around, Democrats will need 6 votes from Republicans, and they appear to have at least 5—assuming each of the 4 Republicans in the "Gang of 8" and New Hampshire's Kelly Ayotte vote in favor of reform.
Bottom line: It's still a challenge, but the starting point is better than with gun safety legislation. And the Senate still sucks.