If you want relatively seamless sync with Macs and iPhone/iPhone touch, I'd recommend it. It does keep my two Macs and iPhone synced, and I have really gotten to love the push e-mail. It has some rough edges, but they're getting smoothed out. It's the best seamless solution out there. It also has been conceived very well. After a rough start in July, all the sync services have now worked 100% for me during the last few weeks. Check out this series for a good technical overview of the service as well...
http://www.appleinsider.com/articles...bile_push.html
http://www.appleinsider.com/articles...bile_push.html
http://www.appleinsider.com/articles...ry_google.html
http://www.appleinsider.com/articles...hone_mail.html
http://www.appleinsider.com/articles..._calendar.html
http://www.appleinsider.com/articles...rver_apps.html