Probably the hottest category in electronics this holiday season is the smartphone -- currently popularized by iPhones, BlackBerries, Palm Centros and others.

I'm constantly asked which one is best. My answer is always the same: That depends. Most smartphones include very similar features like a video/still camera, Internet access, music file/video playback, instant messaging and Bluetooth, with some also including Wi-Fi and GPS. Sometimes the differences depend on which design you prefer to carry in your pocket.

First and foremost, most people want a smartphone to access their email. Which smartphone you choose should depend on what kind of email you need to access: POP (Post Office Protocol), IMAP (Internet Message Access Protocol), BlackBerry, Microsoft's ( MSFT - Get Report) Windows Enterprise or any other imaginable. Your email at work usually determines what kind of corporate system you'll need to use, although many smartphones (but not all) can now handle multiple e-mail systems.( Photo gallery: Smartphones)

So which smartphone should you buy? Here is my quick guide to the 10 best smartphones currently available. All prices quoted are with a two-year service contract.

Apple ( AAPL - Get Report) iPhone 2: ($199/8GB, $299/16GB, AT&T ( T)). What can one say about the iPhone? Although not the best in every category, the iPhone is still the one to beat. It is a nearly perfect package of hip, cool, and serious handheld computer. I wish it had a more powerful processor with added system memory, much better battery life, cut/paste functionality and a universal corporate email system (one that handled BlackBerry email directly without having to channel it through a Windows Mobile server). Phone's operating system just upgraded to version 2.2, which includes some very nifty features).

BlackBerry Storm: ($199 after mail-in rebate, Verizon). Absolutely the best BlackBerry ever. The handset sports a unique touchscreen where the entire screen acts like a giant button and pushes in when you press it. Great camera, music player, GPS, stereo Bluetooth and lots more. Like all Verizon ( VZ - Get Report) phones, it lacks Wi-Fi, so all data goes through Verizon servers. Research In Motion's ( RIMM) Storm is a possible iPhone killer for all the BlackBerry addicts on the planet.

BlackBerry Bold: ($299 after mail-in rebate, AT&T). RIM's new non-touchscreen device. The new BlackBerry interface is clean and easy to master. Everything works as expected. Includes Wi-Fi. If the Storm didn't exist this would be the top BlackBerry.

BlackBerry Pearl Flip: ($149 after mail-in rebate, T-Mobile ( DT)). The first flip BlackBerry is an absolute gas. Does everything its bigger siblings does and more. Includes T-Mobile's phone-calls-via-Wi-Fi option, which lets you make all the calls you want, via Wi-Fi for $10 additional per month. Small and light, this is the most portable BlackBerry ever. And one of the cheapest!

T-Mobile G-1: ($180, T-Mobile). This is a terrific first try for a touchscreen phone using Google's ( GOOG - Get Report) Android operating system. This "Gphone" handset had great ergonomics and a slide-open QWERTY keyboard. Amazing Google map feature bonds with the internal GPS and lets you see a street view of where you're standing, which actually moves with you in any direction. If you like using Google mail (and Google everything else for that matter), you will love the G-1. Phone comes in black, copper and has just been released in a very pretty white color (my favorite).

Samsung Instinct: ($130 after mail-in rebate, Sprint ( S - Get Report)). This smartphone won all sorts of awards at the CTIA 2008 show and is a crowd favorite. If you're a Sprint customer, the Instinct is a great choice for a smartphone. Your email choices are limited at POP and IMAP, but for many users that's not a problem. Sprint offers a $100 "everything" monthly plan that could be a good choice, too. Sprint is currently offering free shipping and activation when you order new service. Sprint's 3G service has vastly improved in the past few years. Just think what happens if Sprint releases a 4G/WiMAX Instinct!

Palm Centro: ($50-$100, various carriers). The "baby" Palm is an absolute winner. It is small, cheap and does nearly everything that all the "big guys" can do. The QWERTY keyboard is small but amazingly easy to use. This is a great product that came at the right time for Palm and for needy smartphone users everywhere. Don't be fooled by the small price -- this handset is a little powerhouse.

Palm Treo Pro: ($549, unlocked). This beauty has no U.S. carrier, so you have to buy it unlocked from on the Palm Web site and pay the full, unsubsidized price. That's too bad because this is one heck of a smartphone. It is a Treo-to-the-MAX). It is a GSM world phone, which works and feels like a precision instrument. I wish I could let all my readers touch and try one -- I'm pretty sure you'd like it. Like the Centro, it can handle corporate Microsoft Exchange Mail.

Nokia N96 ( NOK): ($776, unlocked). Another case of a great cell phone and no carrier to handle it here in the U.S. The N96 is a media giant. The stupendous screen slides up to reveal the keypad. It slides down to display the media controls. The built-in video/still camera is 5 MP and sports a Zeiss lens. It also works flawlessly worldwide. This is a terrific smartphone disguised as a cell phone.

LG Incite: ($200 after mail-in rebate, AT&T). You haven't heard much about this phone because it's a brand-spanking-new design. It's also LG's first Windows Mobile smartphone. It's also completely touch-screen controlled. I just started testing it, and I have to tell you that it's a really great phone. The touch screen isn't as advanced as some of the top contenders on this list, but overall this is a slick, fantastic-looking device. Full write-up is coming soon.

Gary Krakow is TheStreet.com's senior technology correspondent.