I've been browsing around other forums seeing what the overall impressions are of the Destiny Alpha (need my Destiny fix now that the Alpha is gone).

NeoGaf had a pretty interesting thread on their forums. They specifically asked people to post their "hype level" (0-10 scale) before and after playing the Alpha.

The original poster provided some stats, but I decided to collect and enter them all myself to get a better visual representation of the data.

At the time of my data collection, the thread had 760 posts. I only entered the data for posts where people provided numbers for both pre- and post-Alpha hype levels. If they only provided numbers for one or the other, they were not included. Hype levels above 10 or below 0 were entered as 10 and 0 respectively. All fractional scores were rounded.

Here are the basic stats similar to what the OP provided but updated with my data set from that thread:

Number of responses included in this survey: 533

Average interest level BEFORE alpha: 5.6 / 10

Average interest level AFTER alpha: 8.3 / 10

Percent of people whose interest in the game INCREASED: 81.2%

Percent of people whose interest in the game DECREASED: 12.8%

Percent of people whose interest in the game stayed the same: 6.0%

I wanted a better visual representation, so I made this chart:

Lastly, I examined the amount of people who completely changed their minds about Destiny. This means they had to jump 5 or more Hype Levels in either the positive or negative direction.

Number of people who became 5+ levels MORE hyped: 128

Number of people who became 5+ levels LESS hyped: 12

It's clear the Alpha made a very significant positive impact on people's perception of Destiny. Bungie should be proud of what they accomplished by releasing the Alpha out into the wild. It has definitely generated a lot of excitement in the gaming community.