"Bloggitus" isn't right; it would be something like "having blogged" or "being blogged about". Also, that double g is very un-Latin. I'd think something like "B

"Bloggitus" isn't right; it would be something like "having blogged" or "being blogged about". Also, that double g is very un-Latin. I'd think something like "Blogamus" or "Blogimus" depending on how you want the verb to conjugate; the former feels more natural to me. If you want something a bit more Cartesian, you could make the verb "blogito" rather than "blogo", in which case you need "blogitamus" instead of "blogamus". I'm not convinced it's sufficiently nearer to Descartes to justify such a barbarous coinage :-). The rest is fine; "ergo sumus" is indeed the right pluralization of Descartes's "ergo sum".