In your theme’s activity/entry.php file change:
<?php if ( is_user_logged_in() && bp_activity_can_comment() ) : ?>
<a href="<?php bp_activity_comment_link() ?>" class="acomment-reply" id="acomment-comment-<?php bp_activity_id() ?>"><?php _e( 'Reply', 'buddypress' ) ?> (<span><?php bp_activity_comment_count() ?></span>)</a>
<?php endif; ?>
to:
<?php if ( is_user_logged_in() && bp_activity_can_comment() ) : ?>
if ( my_bp_activity_type_is_new_forum_post() ) {
<a href="<?php bp_activity_thread_permalink(); ?>" class="acomment-reply" id="acomment-comment-<?php bp_activity_id() ?>"><?php _e( 'View Post', 'buddypress' ) ?></a>
} else {
<a href="<?php bp_activity_comment_link() ?>" class="acomment-reply" id="acomment-comment-<?php bp_activity_id() ?>"><?php _e( 'Reply', 'buddypress' ) ?> (<span><?php bp_activity_comment_count() ?></span>)</a>
}
<?php endif; ?>
and add the following to your theme’s functions.php file:
function my_bp_activity_type_is_new_forum_post() {
( 'new_forum_post' == bp_get_activity_type() ) ? return true : return false;
}