A blog is discussing if it is possible to get a boost to your SERPS by having an SSL certificate on your domains - even if you then make absolutly no use of the certificate. Its presence alone is the factor - as you are deemed more trustworthy than other websites. I guess the cheap $99 certificates will do the trick and might be worth trying out for a tiny boost. http://www.ianvisits.co.uk/blog/2006_12_05/ssl-certificates-update/
I checked that blog out. Frankly I don't think it will have any impact on the SERP's. It goes against the general logic of what SE's are all about. May be some SSL site owned members can say more about this one. Abhilash
In some very small way, I could see them helping. I don't think anyone has ever really tested it at all, but I could see where the claim could be made that if you own an SSL certificate, you're less likely to be a spammer, so more weight would be added to that domain.
IME i had a site with ssl, i submitted it with the https like crazy everywhere and obviously my pr has been grey for the past year, so i changed the landing page to be normal http, and then any action from there goes to https, this upped my site pr to mediocre 4, however for the search term, i am at the top 10, so it did not affect me, p.s. if you need cheaper certificate for 29.99 try dynadot.com my domain registrars, could save you $70 IMO
It is not about submitting a site as https, but how simply having a certificate associated with your website is a "vote of confidence".