I would use both. The more quality work you do the better traffic you can generate. You might have to develop a productive blogging habit. It always pays off: more links and more traffic.
Blogger may do better as far as a good backlink, if you're regularly updating it. Squidoo seems like it can be good for organic traffic. But I suspect that Google is discounting Squidoo lenses, as I watched mine drop from PR2 to PR0. Maybe it would help if it's regularly updated and content added. Personally, I've never seen any traffic from Squidoo.
Squidoo gets my vote too. It's usually MUCH easier to rank well with a Squidoo lens for a specific phrase. However, if you're trying to tap a whole niche(dozens of keyword combinations), you might be better with a blog. Although in that case I probably still wouldn't pick blogger, I'd try a hosted wordpress blog.
I would suggest that you run a proper blog if you plan to write lots of articles about a single topic, or if the articles have a sense of chronology. Squidoo is good for unrelated articles that promoting individual concepts or products.
How long does it take to get squidoo lenses indexed. I made one about a week ago and its still not indexed. I have digged it, stumbled it and put in on my sig.
Then it's just a waiting game. On the other hand if it was relying on scraped content the wait could go on forever.
What about doing this... 1. Squidoo page for every affiliate product you promote 2. Blogger blog for each set of niche related affiliate blogs 3. Hubpages pointing to each of your niche blogger blogs/squidoo pages/content site 4. Your own content site for each niche that you are promoting affiliates with... the content site would also be able to run adsense etc. Basically the more ways you find to promote your sites/products without spamming them, the better the chances of you covering more keywords for the related product. You shouldn't just duplicate content on each one of the methods to promote your sites/affiliate products, but you should look at covering more keyword phrases by producing more varied blogs/pages etc.
i would use both and either inter-link the 2, or have one pointing to the other. either way, both can rank very high in the SE, but you need to update either one quite often. at least once a week seems to be the best.
Try using this ping tool to ping your lens across the blogosphere. It's been optimised for Squidoo lenses (only), and I think it may help get new lenses indexed by search engines. Let me know if it works... PS: Re-publish your lens first.
Be careful how it's written and how often you link to the same site. As the hub could be flagged for being overly-promotional.