You should use the old "it'll enhance our marriage" line. I've only been married for half a year or so - and this argument/suggestion has gotten my foot in the home theater door nicely. She's given me a $5,000 budget, for everything, from soup to nuts (I will need to buy a complete new system, including TV, reciever, cables, SPEAKERS!!!!, etc.)
I keep telling her how much quality time that we will be able to spend, cuddling on the couch, enjoying our favorite movies and TV. This, I tell her, will enhance our marriage.
Now, she knows that I am just tryingto be cute when I say this, and I know that HT will not enhance oru marriage, but, it a nice way to contextualize the purchase with the relationship. She also feels like she's being a trooper for letting me buy "men's" toys (even though she knows that she'll enjoy it as much as I will).
Every woman has a key that will open her up to suggestion. Mine may not work for you (because my wife wasn't very hard to convince on this issue). The trick is to make her recognize what the purchase will do for her and the family. I suggest buying a HT for the new baby, so that when she's little, the whole family can watch movies at home, just like they were at the movies!
