Using hashtags in listings

[Bahram Soltanirad]

Nowadays, using hashtags are so common in social media networks like facebook,twitter,google plus,...
So, i think about a way if user or admin can define hashtags in listings.

Users, can simply add hashtags in description or title area. Actually, i am not sure about effect of hashtags in title.
But there is no way for admin to automate adding hashtags.

So, i think about adding a new field like hashtags in AP/Categories.
Then admin can define hashtags for each category separated by comma. like sell_a_car,buy_a_car,used_car,... in cars category.
If a use add a listing in cars category, then system automatically add #sell_a_car #buy_a_car #used_car as hashtags to the end of description field. So if the user or admin post the listing in facebook, twitter,google plus ... by using auto poster plugin or social media links in listing detail, it will post hashtags too.

I am not sure how important are hashtags. Actually i am not even sure about positive effective of tags (using tag cloud plugin) too.
If they are useful for SEO and SERP.
It is just a recommend for discussion.