yiotta

I found this works in my WP 3.0 theme (not twenty ten, but similar, so YMMV):

In functions.php, find the section referring to the page_navi: in my theme, function page_navi.

Locate at the bottom of that paragraph of code

$prev_link = get_previous_posts_link(__('Newer Entries »', THEME_NS));
        $next_link = get_next_posts_link(__('« Older Entries', THEME_NS));

Comment that out and add instead
if(function_exists('wp_pagenavi')) { wp_pagenavi(); }

So, altogether in my theme it looks like:

function art_page_navi($title = '', $comment = false) {
    $prev_link = null;
    $next_link = null;
    if($comment){
        $prev_link = get_previous_comments_link(__('Newer Entries »', THEME_NS));
        $next_link = get_next_comments_link(__('« Older Entries', THEME_NS));
    } elseif (is_single() || is_page()) {
        $next_link = get_previous_post_link('« %link');
        $prev_link = get_next_post_link('%link »');
    } else {
        if(function_exists('wp_pagenavi')) { wp_pagenavi(); }
		/*$prev_link = get_previous_posts_link(__('Newer Entries »', THEME_NS));
        $next_link = get_next_posts_link(__('« Older Entries', THEME_NS));*/
    }

HTH. I’m not much of a coder, but it works for me (needs styling, though).

Did you find your answer? I was having the same issue, and found this helpful article: http://www.thewpmag.com/quick-projects/replacing-header-text-with-an-image/

Be sure to read the 1st 2 comments, too, or you will miss an important bit of info.

In my case, I used this CSS:

#header {
	width: 900px;
	height: 80px;
	float: left;
	background: #9abc21 url(images/header-bg5.png) no-repeat left;
	position: relative;
	border-color: #FF9900;
	border-style: solid;
	border-width: 0 0 4px 0;
	padding: 0 30px;
}

h1 a {display:block; text-indent: -9000px;  width: 700px; height: 80px;}

And this markup in the header.php:

<div id="header">
		<h1><a href="<?php echo get_option('home'); ?>/"><?php bloginfo('name'); ?></a><span><?php bloginfo('description'); ?></span></h1>
		<div id="search">
			<form method="get" id="searchform" action="<?php bloginfo('url'); ?>/">
				<input type="text" value="Search..." name="s" id="s" onfocus="if(this.value=='Search...')this.value=''" onblur="if(this.value=='')this.value='Search...'" />
				<input type="submit" id="searchsubmit" value="" />
			</form>
		</div>
	</div>

Notice I was able to keep the text without showing it (for accessibility and search engines), have a clickable image as a background, and add a search box on the right without it being part of the clickable area.

Anyway, hope that helps.