Mashable I would advise against. It's full of fluff articles, and sometime a year or two ago had the inexplicable idea of turning into a social network itself. It's a mess of a site and its writing is no better.
Though I don't follow many blogs anymore, period, R/WW writes fewer articles, but it tends to do a much better job with making sure the articles it DOES write are good. It's fairly high-quality.
Mashable sucks a lot, their posts are just derivative of whatever PR piece is sent to their email. They implemented a social network to get them more pageviews but it's now turned into a porn den.
VentureBeat started out by just reporting VC money and so on but switched. I liked him when he was with Mercury News but I haven't really been visiting his site as the other ones pretty much covers it.
Allen Stern wants to be like Michael Arrington and he's done a good job thus far. He breaks news every now and then and provides great analysis.
Silicon Alley Insider is shaping up to be a great tech news source. Topical, on point, and constantly updated.
And as much shit as Valleywag gets around these parts, they're still a top read in my book if you're an outsider in the Valley and want to pretend you fit in.
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