We've had a lot of discussion around here about submissions because it seems that some engines are penalizing sites submitted to them through the free AddURL form.
I would reccommend for you to spend some time reading around the forum and you will find a lot of submission tips regarding issues such as this. You can also you the site search option at the top left of your screen.
Personally, regardless of whether you choose to submit those pages directly, I reccommend that you cross link heavily so that even if you submit the page, the spiders can also find the pages on their own and lift the penalty. This will also help with link popularity.
As long as your subdomains are linked from the index page, they will be crawled by google and fast. The rest of the engines may need some direct sibmitting of these subdoamins as crawling patterns tend to be erratic in engines not mentioned above (Northern Light does a good job of crawling also, they just don't bring in a lot of traffic).
I read on searchenginewatch that for large sites like mine it's better to use the subdomains because they search engine will only crawl a certain number of pages, and by splitting the site up it causes them to crawl more of my site than normal, that is why I was ansking, and thank you guys for the responce.
To strengthen sub-domains I try to get as many incoming links spread over them, so as to intensify the support of the root. I donít spend much time submitting to any of the engines. I of course do the initial submissions to Yahoo, ODP, Looksmart and then Inktomi, and all except for ODP I pay. With sub-domains, Iíd get as many strong links pointing to them as possible. If not Yahoo and ODP then I submit to as many vortals, portals, themed and business directories, and hubs of all sorts, that I can find. Thatís about all the submitting I do.