I used Tags on a number of sites and found its tagging method to be very effective at attracting Google.
I tried a couple of the newer tagging engines on 2.5, and it just wasn't generating the same type of results.
I'm finding a few little quirky things, but I'm sure you're on it. Keep up the good work!
I used TweetXT for a long time because it generated HTML with links in the source code. Very happy that your module also does this. It's so important for SEO purposes!