Index.txt - blocking pages allows others to become indexed ??

I have 1000 pages listed for my forum, but a lot of them are really unwanted things like profiles, tags etc.

If I block them all with robots.txt will this mean the amount of pages I have listed will reduce or will google find more topics to take the number of listed topics back up to 1000

I can't say with assurity but would suspect that the number of topics would increase.

In the end, it doesn't really matter as those pages add no value to the index so IMO it's best to block... printer friendly, profiles, search, user cp, etc. Go ahead and nofollow them and let us know.

Would you no follow tags as well ? Im trying to work out if they are of any use for seo purposes

Yes, I use the nofollow on all of my links to similar pages. As far as page count/SEO benefit, you'll be much better served by focusing that PR on pages that may deliver value to searchers.

Thanks foghorn.

Think Ill just dissallow to anything with ?action in the url.

will this work as a wildcard to google ?

User-agent: *
Disallow:/forum/?action*

User-agent: *
Disallow:/forum/index.php?action*

Just a quick update here.

The pages do seem to be dropping out the index. The problem at the moment is they arent being replaced by more appropriate pages. Ive dropped from 1000 forum topics listed to around 300.

I hope I have got the coding right in robots and have not somehow dissallowed all forum pages.

Nearly all the tags have now been dropped from google. I went from 1000 pages listed down to 200 (ish). Then I woke up one day mid dec and I had 1000+ pages listed.

Sadly yet again, they were mostly unwanted listings. Google was listing all my wap2 pages. So I added them to my robots.txt

Now WAP2 is slowly being removed. Im back down to about 300 pages listed. Im hoping to wake up soon and find 1000 pages of useful forum topics/content listed.

If google finds anything else to index from my site other than the topics, then it wont be a happpy new year round our house. Why does google list everything but what you want it to ??

Well what a slow process. Its now 4 month since my initial posts and things are just coming right. According to a site:domain search I have 800 pages listed and all of them appear to be forum topics. This has only come right in the past week.

I had read that google was having problems indexing new pages. Maybe this is why it took so long ??

One thing Ive noted is that with the increase in forum pages, came an increase of bounce rate. Jumping from low 20% to over 30 %.