Hi Cristine,
Hope you've got found your answer but I just wanted to also give my input.
Whilst they do pass some "link juice" its more akin to creating a separate site meaning double the work, this can be fine if that's what you want but for me its a lot easier to create e.g. www.yoursite.com/blog then any links created also benefit your site as well any users can also browse your site straight from your blog pretty easy etc. You can see what Matt Cutts said about a similar subject way back in 2007 here - https://www.mattcutts.com/blog/subdomains-and-subdirectories/
Regarding your second point if it's getting found and is working that fantastic but what is the likelihood of this? If you're running an email marketing campaign and relying on direct traffic this may not be an issue but I don't know of many sites that rank purely on their content alone from the start you can give yourself a bit of a boost from your main domain via a subfolder.
In Summary- If your site is getting found, getting exposure and all that jazz fantastic give your self a pat on the back, however if not there is nearly double the work on trying to get a subdomain to rank compared to having it on your main site, this is fine for some of the experts but if not I'd recommend you give this a try first and if you want you can move it onto its own subdomain at a later date. In terms of metric unfortunately they do matter if you're after exposure and organic exposure.
Finally you can also see (via Q&A) some example here - http://moz.com/community/q/moz-s-official-stance-on-subdomain-vs-subfolder-does-it-need-updating
Hope that helps and best of luck with your blog.