You might clarify if you are talking about "the real world" or "the web world".

If you have a real product and a real company, the convention is to make a single press release, which you release through one more more legitimate press-release agencies (such as, say, PRNewsWire). You will typically have to pay (several hundred dollars) to release through the agency.

You would also archive the press release on your web site, in your "press" or "investor relations" section (the latter if a public company).

If you're talking about some other kind of new-agey "press release", I have no idea. Lord knows what people are calling a press release these days.

thanks jtara. by PR i mean good old PR that will let you know what kind of changes we did and all that. I will be placing that article in news section of the website but was not sure if that particular PR should be different from the one i would be giving to PR newswire.

by your reply i am understanding that same PR article is fine

Nothing wrong, of course, with posting additional supportive material on your web site. Indeed, there usually will be plenty - catalog listing, data sheet, white paper(s), etc. And of course a front-page blurb.