Anyway, about 6 weeks ago I decided to go after a 3-word longtail keyword in this niche that was very specific to the products I sell. It was the manufacturer's name + the general name of the products. I used my favorite keyword research tool (Micro Niche Finder) and determined that this phrase had very little competition and was searched for a decent number of times per month (about 1600). Since what I sell is only this manufacturer's products in this particular industry, I figured the traffic would be ultra targeted and ready to buy. I was correct. I just made a sale today and the keyword the guy used to hit my page was this longtail one. I know because I asked him if he remembered what he searched for and he did.
So that's one big reason why you should target longtails in your marketing plan. If you plan it out a bit and choose the longtails that meet certain criteria - decent number of monthly searches + low competition + probably a 'buy now' phrase - you don't need a ton of traffic to make some sales.
There's another big reason to target longtails: search engine rankings. This keyword I've been talking about is currently #3 at Yahoo, #2 at MSN, and #12 at Google. And the site is only about 4 months old. The page with that keyword is only 6 weeks old. All I did to get those rankings was get about 20 links pointing to it. These were all social bookmarks + blog comments + some blog postings on blogs I own.
Here's a key point that I don't think many people are up to speed on when it comes to longtails and backlinks. NONE of the backlinks I've gotten were on related sites. Let that sink in a second. Not one of the links is on a site that has anything to do with this niche! What the links almost all have in common, however, is that the domains (not the URL the link is on, but the homepage URL) are higher PR. Almost all have domain PR's of 4 or 5, and a couple are higher last time I checked. I think this matters a lot with lower competition keywords. I have no other reason to think this particular longtail would rank so high across all the major search engines when it's only 6 weeks old if not for the higher PR sites the 20 or so links I've gotten sit on.
Hope this helps some of you who are struggling getting traffic that's ready to buy!