Mango PR managing director Claudia Macdonald estimates the number of such blogs has quadrupled in the past 18 months, though not all are seeking PR ties.
Pead PR is another high profile consumer PR company being swamped with approaches from bloggers.
Sometimes, PR firms search them out.
An example is Pead's client My Food Bag, which has developed a gluten-free bag specifically for coeliacs.
"We've been searching for bloggers who are either coeliacs or who are advocates of gluten free," says managing director Deborah Pead.
"We have identified six who we will engage with for trials and feedback. Depending on their feedback we may invest in some content creation with them," Pead says.
It's early days yet, but the Public Relations Institute (Prinz) also says there is a constant stream of new blogs. However, that does not mean a wall of marketing money is moving from mainstream media to blogs.
Bloggers are sometimes paid fees from PR firms that work with them on promotions, and small-scale payments from media buyers. However it's still a tiny part of marketing spending.
The key words are intimacy and pinpoint targeting. Bloggers' closeness to readers can overcome their relatively small size, and that can work for some brands.
Sometimes, agencies use bloggers to get their brands into promotions.
There is competition among PR companies, social media agencies and media buyers over who has the closest ties to blogs in this emerging medium.
But, naturally enough, Macdonald thinks PR is front-runner in "owning" blogs as a medium. "Just like print media, to survive, bloggers need to earn income through fees for their work. Contra is not enough to feed hungry mouths.
"Generally this means we provide the product and some assets and they deliver in their own unique way," says Macdonald.
"We've been doing this with radio for years - paying promotional fees for their creative ideas and air time to promote product.
"There is a degree of editorial licence but by no means as strict as advertising, which is completely controlled by the brand," she says.
"Bloggers are really where magazine readers have migrated to," says Macdonald. The blogs had filled the gap when the internet took readers away from niche titles.
However Magazine Publishers Association chairman Paul Dykzeul disputes claims that the growth of blogs is due to the demise of niche magazines.
Dykzeul is chief executive of the dominant magazine company Bauer Media New Zealand, and says niche magazines are doing very well, in this country and Australia.
PR companies, he says, are promoting the idea of using blogs to their clients as a way of getting as much media coverage as possible for nothing.
Selling the silver
In my opinion, there is a danger of blogs built around independence being too closely associated with brands.
Macdonald says the foundation for blogs to get commercial messages across is the same as it is for traditional journalists.
For that reason, she says it is important for bloggers to be very careful to manage their commercial relationships.
Prinz chief executive Simone Bell also says it is important that blogs tell users about their relationships with brands. She stresses that it is the responsibility of the blogs - not just the PR companies and brands - to be open about those ties.
That view might bear thinking about for advertisers and brand leaders. After all, there was the case of the Whale Oil Beef Hooked blog, whose links to public relations campaigns for the Food and Grocery Council came under scrutiny in the Dirty Politics saga.
That association will have reflected on the FGC more than it did on Whale Oil, in my opinion.
Damp squib
Industry claims that Sky TV was hoarding terrestrial TV frequencies have turned out to be a damp squib.
After talk of nationwide terrestrial pay TV broadcasts in the 2000s, the future of pay TV has moved to the internet.
Sky used some of its surplus frequencies for Igloo, a "Sky light" package that included linear TV. And it handed back to the government the frequencies that could have been used for a terrestrial network on top of its satellite service.
Sky chief executive John Fellet says Sky came to the view three years ago that linear TV had peaked, and such channels were not going to be the future of TV - a view that has proven right.
Even past critics of Sky privately say they are now much less concerned by its dominance.
It's true, Sky's hold on the market in the early 2000s might in theory have discouraged alternative pay TV operators from setting up here.
But 20/20 hindsight suggests competitors would have faced intense challenges anyway, from the likes of the global network Netflix.
The other criticism of Sky, through the 1990s and 2000s, was that it restricted competition through its access to content.
The reason, of course, is the business plan, which forces customers to pay for lots of programming they don't want. Most people watch fewer than 10 pay channels.
I asked Fellet if he would ever consider unbundling the Sky package, to reduce the cost.
He was noncommittal but said Sky had already unbundled its sports offering with its Fan Pass offering - albeit at a high price.
Unbundling is highly unlikely, I believe. The basic package is the foundation of Sky's revenue.
But in my opinion, Sky needs to do something to reduce the cost for consumers.
