This is not a big deal. Essentially, BCCI will not provide press accreditation to rediff and cricinfo. This means they wont get badges to watch the matches. They can easily find a way around.
They can still cover events by simply watching the match on tv and reporting the scoring. They can even get seats in the stadium by paying for it and using a laptop or pda to report the events.
Legally, there can be no monopoly on news. BCCI cannot bar some one from reporting news events. There is no copyright or intellectual property in it.
As regards reporters, it might be hard to have a Tony Greg report and give his comments if he is accredited to another press agency and that press agency is barred in its contract with BCCI from allowing it. Its still not a big deal. Get experts to pay tickets and go and watch. There is no law against interviewing a spectator.