Yes--good point! I agree with you---keeping a focus and consistency are key, especially for corporate brands. I do think it's important to be focused as a personal brand as well, but I think the rules are a bit different for a corporate brand versus a personal account or personal brand. IMO, it's a just a matter of degree.
When I'm following a human being, I feel more connected to that person when every tweet isn't laser-focused on their industry. Humans aren't one-dimensional and I think our digital presences should reflect that. If I don't see a little variation, it feels a bit...contrived to me. However, I DO expect lots of links to articles and industry related news from corporate accounts.
Also, I don't need the people I follow to tweet or retweet every Mashable or TechCrunch article out there--I have RSS feeds in my Google Reader for that purpose.
I guess I break it down in my mind like this: Generally speaking, I follow brands, companies, and media outlets for news and for industry trends. I follow individuals for some news (posts from lesser-known sources, for example) but more for conversation, networking, and idea sharing.
Do you agree? Do you think it's okay for individuals to share a wider range of topics, or do you think that's a distraction? Curious to hear your thoughts...